2010 has been a huge year for Facebook – arguably the company’s biggest yet. CEO Mark Zuckerberg was named Person of the Year by Time magazine, a Hollywood movie about the founding of the company was released in theaters, and attracted a great deal of critical buzz. The company launched the "open graph", possibly the most important feature the company has ever implemented, as it connects nearly the entire web to Facebook itself. Then there was the messaging product, the privacy fiascoes, and much more. 

Here we’ll look at Facebook’s year month by month. You won’t find every single Facebook story from the year here (and feel free to add any additional ones in the comments), but you will get enough to get a general idea of what the company’s accomplished over the course of the year, and why Time did name Zuckerberg the person of the year. 

January

It was a good year for Facebook right from the get go, starting when Facebook beat Google (in terms of traffic) on New Year’s Day, according to Hitwise. Also in January, the company launched a Fellowship Program for Ph.D. students, became a sponsor of the Apache Software Foundation, partnered with McAfee, got into customized data centers, and expressed the desire to be users’ news source.

Mark Zuckerberg made some comments related to privacy that raised a few eyebrows, though this was nothing compared to the privacy firestorm he would set off a few short month later. 

Facebook added a feature that lets users reply to comments from their email, added a retweet-like share button, started letting app users get notifications through email, and started giving Facebook Page admins more stats.

Also, rival MySpace started integrating Facebook Connect into its site.

February

In February, Microsoft and Facebook adjusted their partnership, and Facebook celebrated its sixth birthday. The company announced it was approaching 400 million users, and redesigned the homepage. 

During the Super Bowl, more people visited Facebook than any other site. Facebook was added to AOL Instant Messenger, Facebook passed 100 million mobile users, got a patent on news feeds, and was coaxed into opening a new office by the governor of Texas. Facebook announced people could pay for Facebook Credits using PayPal. 

March

In March, Facebook began testing a "promote your post" feature, partnered with Omniture on ad data, expanded its Preferred Developer Program, made its Texas expansion official, and unseated Google as the most-visited site. Yahoo brought Facebook into its own inbox. Facebook tweaked its privacy policy and its search suggestions. 

April

In April, Hitwise dubbed Facebook the most searched on brand in the US, Facebook acquired photo service Divvyshot, and the company clarified its stance on third-party partnerships. The Winklevoss twins (founders of ConnectU) said they would be filing more lawsuits against Facebook. 

Facebook redesigned its safety center, announced its first batch of Fellows, and entered the stickers-for-businesses game. A report came out claiming that more business Internet traffic was going to Facebook than to any other website. 

Then, Facebook dropped the bomb at f8 – the Open Graph and social plugins that would tie the web to Facebook via like-buttons and various other ways for content publishers to draw traffic and encouage engagement from their users.

May 

In May, Facebook was exciting publishers with increased referrals (courtesy of those social plugins). The company announced expansion in Seattle and hired a former FTC chairman. Facebook also announced that the social plugins had already appeared on 100,000 sites since launch.  Facebook introduced new login security features and overtook Yahoo in Display ads. 

As privacy concerns reached an all-time high (courtesy of the Open Graph), Diaspora started to gain a great deal of buzz as a possible alternative to Facebook. Yeah. Meanwhile, Microsoft previewed its hotmail upgrade with Facebook integration. 

Facebook reached a fiver year deal with Zynga, and launched a new mobile site. The company gave people a way to turn off third-party service and scheduled a privacy briefing for Congress. Then it acquired Sharegrove and introduced new privacy settings. 

The official Facebook SDK for Android was released, and Demand Media made a move which would greatly expand Facebook’s open graph. Facebook began calling for beta testers of a Q&A product. 

June

After so many privacy stories about Facebook and discussion of account deleting permeating the media, it was looking like people were not so eager to delete their accounts after all. It was also revealed that Facebook had seen a 400% rise in advertisers since early the previous year. 

Facebook launched a new politics destination and an official Facebook and Privacy Page. Yahoo launched a new integration with Facebook. Bing offered a new take on social search with Facebook. Facebook improved analytics. 

Facebook launched a feature that let users "like" comments. Zuckerberg said it was "almost a guarantee" that Facebook would reach a billion users. Then the company hired a White House economics expert. 

Facebook indicated that "all Open Graph-enabled web pages will show up in search when a user likes them." The company’s COO made the infamous statement that email was "probably going away":

The company geared up for a big expansion in India, and snagged Google’s Chrome Engineering Director (one of many Googlers to defect to Facebook). The company launched the API Console to make the Open Graph  API simpler, entered a five-year agreement with CrowdStar around Facebook Credits, and revealed some details about how it handles spam. 

July

Facebook began testing facial detection for tagging in photos, began offering new suggestions for users, acquired a travel recommendations firm, and it was revealed that it would close its gift shop.  Microsoft integrated Facebook into Outlook. 

Some guy claimed he owned the majority of Facebook in the latest of Facebook’s many legal battles. The company detailed its mobile strategy and scored low in user satisfaction. Facebook then hit the 500 million user mark officially, while the company received a billion hits per day. Mark Zuckerberg declared that he would not see "The Social Network" though he eventually caved. 

Facebook tweaked the homepage navigation, made improvements to the like button, simplified the account deletion process, and debuted the Q&A product in beta. Amazon launched a powerful new Facebook integration. Playdom entered a deal with Facebook on Facebook Credits. 

August

In August, it was said that Google’s social plans had fallen into Facebook’s hands. Facebook was to double the size of its custom data center. Facebook took its privacy adjustments mobile and acquired  Friendster patents. Facebook and AOL considered an online ad deal. Facebook adopted a single-page approach to displaying photos. 

The company acquired the lead designer from Spotify and launched Facebook Live to broadcast live announcements and celebrity events. The Facebook Notes feature got tags and improved formatting. The Facebook Panic button reached 55,000 downloads. The company acquired a search company with Google connections.

Facebook launched Facebook Places, moved toward OAUTH 2.0 and iFrames, while dropping the app tabs from profiles. The company also acquired Hot Potato. 

It was discovered that you can’t block Mark Zuckerberg from your Facebook profile, and some examples of Facebook penetrating the physical world were seeing the light. The company tried to own the words "Face" and "Book". The company partnered with a Venture Firm to support startups. 

A "photo memories" tab was spotted attached to Facebook Places, the company sued a Teacher Resource site for using the word "book", and got a patent on click-based search relevance.

MySpace started letting users sync their accounts with their Facebook profiles. 

September

Facebook started testing subscriptions and announced Remote log-out. They also started testing a feature that would make Facebook more valuable to search. Facebook added an ad impressions counter. Zuckerberg announced Facebook support of Change the Equation.  Facebook also made changes to its "rejection" system. 

Facebook launched features related to controlling game updates seen in the news feed. Zuckerberg was named the 35th richest person in America, then he announced Startup:Education. The company launched a feature for Page exposure. "Likes" officially became more important to search, and Facebook became second only to YouTube in video viewing. 

October

The Social Network opened in theaters across the US at the beginning of October, and it ran away with the Box Office. Facebook launched new features for photos. Mark Zuckerberg appeared on an episode of The Simpsons:

Facebook announced the ability to download all your Facebook info into one file, the Applications You Use Dashboard, and a new version of Groups. The company made a deal with Bing for the search engine to include Facebook info in searches. Skype launched Facebook integration. 

Facebook was accused of a user ID privacy breach, and Photos went drag-and-drop. Facebook created individual pages about users and their friends, and made a deal with Yandex.

November

Facebook provided users with election resources and announced Single Sign-On, a location upgrade, and the Deals Platform.  A report indicated that Facebook topped eBay in value. 

The company announced its new social inbox and Facebook email addresses. MySpace made a joint announcement with Facebook in which MySpace would have more Facebook open graph functionality. Facebook started asking users to set Facebook as their homepage. 

The company’s valuation hit $50 Billion, and Bing added Facebook integration to shopping search results.

December

In December, Facebook announced that promotions would no longer require approval or $10,000. The company was said to be renting space on Madison Avenue, the company redesigned the profile page, revealed as Zuckerberg was interviewed on 60 minutes. 

The company planned a hiring spree in Ireland, added more privacy controls to mobile, and announced the Hacker Cup, while winning the "Best Place to Work" award.

Facebook launched a significant upgrade to its Android app to include push notifications and chat. Zuckerberg was named Time’s Person of the Year, and the company announced its facial recognition feature. 

Bing started using the Facebook data right in its main search results, and Facebook launched a new registration tool for site owners. We launched a WordPress plugin that harnesses this, by the way.  Facebook launched new filtering options for the news feed.

Much of Facebook’s usefulness comes from third-party apps and sites that have implemented Facebook into their own functionalities. So as much as Facebook has accomplished itself this year, there are so many other reasons Facebook is changing businesses and lives based on the work of others. Share some of your favorite Facebook apps or integrations in the comments.