It looks like the contract between Microsoft and Rockstar has expired - they'll have to update their website.
Sony are so pleased they posted a welcome message on their website - admitting that Grand Theft Auto IV: Episodes from Liberty City was one of the most requested game on their site...
The release date has been set for March 30th and it will cost $39.99, a lot more than The Lost and the Damned at $19.99, the previous episode release.