The keyboard? It rocks. The screen? Beautiful. The trackball is just the right amount of gritty, so your finger sticks to it and doesn't slide off onto the keyboard. The instant-on OS? Classy.
The keys are small, but just the perfect amount of small—you'll only have a problem if you have fingers the size of fried carnival pastries. It took me about 15-30 seconds of mistyping to adjust and type just about perfectly, though your hands won't feel as loose as they are on a full size keyboard by means. They're really punchy, though shallow, too. Overall, good. The trackball is a little oversensitive, but adjustable too. What I do hate are the mouse buttons. They're too small and not distinguished enough, so easy to miss. Oh, and it's a smudge magnet.
The form factor looks weird in the press shots, but in person, it works—incredibly well. It's very clearly a Porsche compared to the Chevy-esque standard netbook. In fact, Sony guys insist it's not a netbook, which is true. It's officially throw-it-in-your-bag-and-forget-it-sized, which netbooks are not.
I like the instant-on OS. It's essentially a Sony XMB that gives you access to photos, internet and movies, much like other instant-on OSes, but the P's seems exceptionally classy.
Every SKU has the same 1.33Ghz Atom inside (the Z series not the pokier N)—not incredibly speedy, and 2GB of RAM, which lets them all run Vista okay. Screen is, duh, gorgeous thanks to that incredible pixel density. The built-in 3G is Verizon only, and they wouldn't comment on a GSM version. Oh, and that $900 pricepoint? That's for Vista Home Basic—you've gotta drop a grand to get real Vista. Otherwise, the 4 different SKUs vary based mostly on storage—60GB starting up to a 128GB SSD in the $1500 model.
You'd almost think you could work on it, but we're not so convinced yet—that'll take some much more extensive hands on time, a couple days at least. At the very least, you'd have to widen and shrink your workflow. But we're definitely curious to find out. Overall, it's certainly an interesting machine—not a netbook, UMPC or laptop, but something in between all of those. What exactly that is, we'll have to figure out in the longer haul.