Update: Retweet.com is now live.

Original Article: First Twitter ignited the URL-shortening service fire, and now a similar phenomenon appears to be happening with "retweeting" services. Retweet.com is reportedly set to launch today.

First of all, if you are not a Twitterer, you may be unfamiliar with the concept of retweeting. Basically, when someone updates their status on Twitter, that is called a tweet. When someone likes that status and wants to share it with others, they will at "RT" (for ReTweet) and the user’s name typically and post the same update. This is usually done with Tweets containing links, so naturally it provides a good, viral means of link exposure.

So far, a service called Tweetmeme has pretty much ruled this area of content sharing. What it does is supply content providers with a button that users can easily click to share that content on Twitter. The button then provides an ongoing count of how many times an article has been retweeted. You can see one at the top of this very WebProNews article.

Retweet.com is now swooping in to try and capture this market dominated by Tweetmeme. In fact, Mesiab Labs, who is launching Retweet.com even called out Tweetmeme by name. Not only does Retweet.com make for a powerfully branded domain for such a service, but the company is also launching with a $10,000 contest to inspire people to use its service.

The really interesting part of this story to me though, is the timing of this launch. Just last week, Twitter itself announced an initiative called "Project Retweet," in which the company plans to bring the concept of retweeting right to Twitter.com and the Twitter API. This means that people using Twitter on the web should be able to easily retweet something from their stream, and apps all over the web will start incorporating retweeting into their interfaces.

At this point, it’s hard to say how relevant services like Tweetmeme and Retweet.com will remain. Considering that they offer services for content publishers themselves, they will probably still have a place. They may even be helped by Project Retweet just because it will put the concept of retweeting even more into the spotlight.

And don’t be surprised if you start seeing a lot more of these retweeting services popping up in the near future. Everybody and their grandma will likely be offering one by the end of the year. It will be very much like the URL-shortener. Some will have different spins, and may entice different groups of users, but Tweetmeme has an established presence going for it, and Retweet.com has that powerful brand name. These two should have the upper hands.

According to Mashable, Retweet.com should be going live around 12pm Eastern Time today.