The Vaio S1 sports a tilted 9.4 inch screen (like a Notion Ink Adam) on top of a Tegra 2 processor. It will feature a "Quick And Smooth" (lame name) UI implentation, a more or less Windows Phone 7 tile like experience as an alternative to the stock Android Honeycomb (Android 3.0).
Sony also hinted an S2 dual screen pocket tablet. This video you should reveal it all.
Official press release can be found here: Presscentre Sony.