I got to play around with the Vita a bit, and think it's a cool piece of hardware!
There's a lot to poke around with even before loading a game. The introduction movies are very nice, and the Welcome Plaza offers a good primer to how the thing works.
I went to copy the PSP version of Little Big Planet from my PS3 to the Vita and hit my first snag - the devices weren't talking to each other. But I found the SOLUTION - the Vita has to be plugged into the PS3's first (#1, left) USB port.
It doesn't work on the #2/right USB port. I hope this helps someone else from the frustration I had, and I would guess this is probably RTFM.
I was surprised to launch the "Near" app and see so many people within 6 miles playing a Vita! Our town is medium sized, and I don't live in the most populated, nor the wealthiest area, but saw about 7 people who played that day.
So I poked around a bit, getting used to the UI - which is fine. Launched the PSN Store, or whatever it's called now, and was pleasantly surprised to find demos for many of the games available. It's cool that downloads can happen in the background while doing other things, so while I was downloading the Rayman Origins and Dungeon Hunter Alliance demos, I also played a bit of wipEout2048.
Speaking of wipEout 2048 - I couldn't figure out where to put in my online pass that came with the game...? I didn't really pursue it much, but it isn't really apparent how to do this, which might be bad design. But the game looks good and plays well.
Also played a bit of Little Deviants, which is what everyone says it is - tech demos that use all the Vita's features (front and back touch, cameras, etc..), wrapped in a game. I found it fun, but YMMV.
I haven't cracked open Uncharted yet, which I'll save once I have some time to sink in and absorb it.
Oh, and the trigger grip accessory seems to work well - it makes holding it easier and places the L-R buttons is a better position for my hands, which are two big wins. The triggers are a little rough to press, but not bad. It also cuts down on portability, and makes the Vita feel a little wider. Playing Deviants it seems like this might make it a little
trickier touching the center of the front and rear touchpads. OTOH, this might be just the learning curve. It's not an absolutely necessary accessory, but I'm glad I have it and will be always using it when I'm at home.
Overall, LOVE the Vita - nice tech (except cameras, which are meh), good built-in software, great screen, feels good, and the games seem to be fun so far. If you are on the fence, give it a try - I think you'll like it!