Over the past year or so, Facebook has made a number of moves, which bring more Twitter-like functionality to the social network. Some question why Facebook would want to become more like Twitter given that it is much more dominant in the social media space, but Facebook sees the growing-popularity of Twitter, and likely wants to make sure it offers everything users want, to keep them around for the long haul.

Over the past year or more, you have probably heard your fair share of people telling you that you need to use Twitter if you hope to have business success. It’s true that there are a great many opportunities and potential benefits to using the service, but do you have to use it? Well, that depends.

Is Twitter Necessary? Tell us what you think.

According to Mike Arrington of TechCrunch, "multiple sources have confirmed" that Twitter is readying the launch of a new set of tools to let third-party sites easily integrate with Twitter. He calls this the company’s response to Facebook Connect.

Today Facebook launched a feature that some would consider long overdue. They now let you reply to comments via email. In other words, when you get an email notification alerting you that someone has left a comment on one of your status updates, you can simply type your reply in the email and hit send, rather than having to leave your inbox, go to Facebook and respond there.

Each month we’ve been looking at Twitter’s growth in terms of new user registration and number of Tweets. Last month we saw a decline in the number of new Twitterers in November continuing a trend that began in July.

In December, however, new Twitter user registrations leveled out. Number of tweets grew significantly, and the number of tweets from new users grew as well, possibly indicating that people aren’t just signing up for Twitter and not using it.

Seesmic announced today that it has acquired Ping.fm. This is a service that has half a million active users posting daily from various devices by sending email, text messages, and chat.

Update: Some Facebook users are reportedly now seeing a new Facebook design that looks like the screenshots here. The design is similiar to the one below, with some slight differences.

Just as many of us get back to work after the holidays, Twitter has some new people starting work with the company altogether. Twitter reportedly has ten new people (most starting today), and some of them have interesting backgrounds, which could have interesting implications for the company’s future.

As we did last year, we have gone back through our archives and picked out some of the most noteworthy social media items we have covered since 2009 began. Now that 2009 is almost over, it was worth going  back and seeing what all has happened.

If you come across missing items, please feel free to share them in the comments.

Update: VerticalResponse CEO Janine Popick has written a separate piece adding 10 more reasons.

WebProNews recently covered a study from Chitika, which found that Facebook was the most valuable social media tool for driving repeat readers to content sites. The study was based on 33 million unique users across Chitika’s publisher network in September. It compared the number of visitors coming from major traffic sources Digg, Facebook, Google, Yahoo, Bing, and Twitter, to the number of times those visitors came back to the referred site.

Update: Ford announced profits of nearly $1 billion between July and September. This is attributed to increased market share and a successful cost-cutting program. I wonder if the company’s social media strategy played a significant role.

Twitter has partnered with Telstra to launch Twitter SMS in Australia.

"As always, it is free to receive notifications and standard text messaging rates apply to sending," says Twitter’s Kevin Thau. "It’s the same pricing as sending and receiving text messages from friends."

Nielsen has shared some interesting findings from its research on how Internet users discover content. The research mainly focused on how content is found through search, portals, and through social media.

There have been many articles written about why to use Twitter, and we’ve certainly published our fair share of them. However, the landscape is constantly changing. New trends, ideas, applications, and features come out, and they further emphasize Twitter’s place in said landscape. Following are some reasons why it is becoming increasingly important to marketers.

Disclaimer: This article was originally written before Google made its announcement, and has been updated to reflect that.

Google and Microsoft have both inked deals with Twitter and Microsoft has also inked one with Facebook to integrate Twitter and Facebook updates into Bing search results. Google will be adding tweets to search results.

Twitter was hacked last night, and when users went to Twitter.com, they were presented with a message from someone claiming to be the Iranian Cyber Army. TutorialsTips has posted a video on YouTube showing what Twitter looked like as it was compromised.

Twitterers in the United Kingdom, Ireland, the Isle of Man, and the Channel Islands will be happy to know that TwellowHood, the Twellow feature that allows Twitterers to connect with people in their own area, is now available in these areas. Until now, it has only been available in the US, Canada, and Australia.

Update 4 : Twitter is now supporting the German language.

Update 3 : Twitter is now supporting the Italian language.

Update 2 : Twitter is now supporting the French language.