Wednesday, Twitter launched a brand new homepage for users before they log-in. The emphasis on the new homepage is to “follow your interests,” as Twitter wants to engage new users to be frequent, active users.  Twitter has now updated their log-out page to promote the use of Twitter on the go with mobile apps.

When you log out of Twitter on your computer, you will now be greeted with a page asking you to “now go mobile.”  You will also be presented will different devices for which the Twitter mobile app is available.  Clicking on any of these options will take you to their respective app page at the iTunes Appstore, Android Market, etc.

The new log out page also contains buttons that prompt “download now” and “Use via SMS.”  The latter redirects back to login, while the former asks users to enter their email address where they will be sent a link to download the proper app for their device.

This new log-out page is reminiscent of when Facebook prompted users to go mobile after logging-out over a year ago.  That venture was extremely successful, as Ryan Spoon points out – Facebook iPhone usage shot up 20% in one week.

A large amount of people still use Twitter.com to read and write tweets, meaning they are not tweeting as much on the go – a fact I’m sure Twitter would love to change.  This new log-out page could help Twitter in two important ways.  First, it simply promotes greater use of their service.  Although Twitter recently announced eclipsing the 200 million user mark, many have speculated that a significant amount of those users aren’t actually active.

Second, it promotes the use of the official Twitter apps as opposed to third party apps that allow access to the service.  In March, Twitter made some changes to it’s API policy and issued a statement telling developers to steer clear of trying to mimic the official Twitter mobile apps.  Major competition exists for how users access Twitter’s core functions, as some research has put the percent of tweets coming from non-official apps as high as 42%.