As you know by now, Sony will be entering the tablet market in a big way. Their Honeycomb tablets, that's two tablets, is looking squarely at Apple and Nintendo. One tablet will be a standard tablet form with a 9.4" screen, the S1 while the S2 will be a clamshell device with two 5.5" screens. Again both will run Android 3.0 powered by Nvidia's Tegra 2 chip.
I'm holding off judgment on the S2 until I see it in action but it's clear that Sony is betting bit in the market but I am excited and hopeful that Sony will have a pretty sweet UI going on.
I reckon that the S2 will be more of an entertainment device along with its NGP. This one-two punch, at least on paper now, has a good chance of hitting Nintendo's 3DS, whose sales have been okay but not really lighting the market on fire, and whatever iPod touch update Apple has planned for the fall.
Ultimately, it's going to be the user experience. Nintendo has made the dual screen form factor work as a gaming machine and Sony is probably betting it can do better with a high resolution implementation.
As for the S1, it's totally an iPad play. I don't get the wedge shape of the tablet but I'm sure Sony has its reasons though they escape me at this time.
Oh, there's one more thing. Price. I think Sony will try to be competitive but Sony has not exactly been known to be reasonable for consumer wallets. But I have always dig Sony. Perhaps, when I win the lottery later this year, I can get myself a new Sony tablet or two along with a new Bravia HDTV and get myself a Sony ecosystem working.
Note: I would like to note that Sony can possibly hit a homer by allowing the S1 and S2 to run Playstation games or join the network. Like I said, Sony can produce amazing consumer products and its Playstation ecosystem is its best chance against iTunes.