Until this morning, Seesmic did not reveal any specific details, sans the fact that this should be based upon enhancing and rebuilding Twhirl. The previous version of Seesmic Desktop was downloaded 1.2 million times, so the authors think they're on the right path.
The Publisher's site only contains a form for your name/e-mail; you are getting a download link in the inbox, rather than a download link on the site itself. Posted screenshots give a glimpse of the new UI [User Interface]. As the developers say, Seesmic Desktop will not be something spectacular and revolutionary, it will not change your life, but rather may improve the way the people use Twitter. During the live video stream, we heard that while there is currently no doubt that TweetDeck is still the #1 desktop app for Twitter, the authors hope that Seesmic Desktop will change the running order.
Seesmic Desktop is a desktop application programmed by using Adobe's AIR, supporting both Mac OSX and Windows platform. Seesmic Desktop also supports multiple twitter accounts, claiming more flexibility than the old Twhirl-based application. The application features navigational bar on the left, multiple columns and plethora of other options. We'll reserve our final judgment until we see the final version.