The rumours are true! Last night in San Francisco, Twitter revealed it’s ‘new look’.

New Twitter features a radically revised two-pane design which allows users to get more information about individual Tweets and Tweeters. The main changes are:

• a new double pane layout
• partnerships with multimedia service providers like YouTube, Flickr and TwitPic and integration that allows multimedia content to appear on screen without opening another tab
• related content that appears on the new pane when you click a Tweet. The details pane shows additional information related to the author or subject. Depending on the Tweet’s content, you may see replies, other Tweets by that user, a map of where a geotagged Tweet was sent from, and more
• mini profiles that appear when you click a username without navigating from the page. They provide quick access to account information, including bio and recent Tweets

The New Twitter preview will be rolling out to users over the next few weeks and, to start with, users will be able to switch between the two versions. The guys over at TechCrunch have already been having a play and, even at this early stage, seem to be pretty impressed.

Does this really matter?

There is an argument for saying that, with so many Twitter users making use of third party apps like Tweetdeck and Hootsuite, the new changes won’t actually make much difference. After all, while there are lots of great new features, they don’t come close to some of the functionality these other apps offer. But we shouldn’t forget that the more casual user will be wedded to Twitter.com and these changes will give them significantly improved functionality. And with Hootsuite recently bringing out a paid version, will this move from Twitter convince more people to go back to the third party app?

This brings us to another interesting point and that is that Twitter users are famously very protective about the service. Remember the new retweets furore or the changes to @ replies. As Twitter employees have said, this is the biggest change the company has seen since it started so there is likely to be some backlash. After all, we don’t like change, do we?

What about businesses?

We’ve all been waiting very patiently for Twitter Corporate which was announced last year but Has yet to appear. Could these infrastructure changes signal that wider roll-out may be upon us?

It’s all about money

Of course the major driver for all of this is the fight for eyeballs and therefore advertising cash. Twitter wants to keep users on it’s site for longer. Until now, Twitter users would have to leave the site to look at pictures or videos and would possibly then get distracted and move onto something else. By keeping all this content on Twitter.com, the social network will hope that it can increase time on the site. Could there also be a suggestion that Twitter might look to begin offering the possibility of previewing webpages in the right pane as well?

Here is the (very slick) official video: