Hey guys the vita is sweet. I picked one of a few days ago but I've only put about 2 hours of total playtime with it.
The system is super sleek, lighter than the PSP 1000 and the screen is huge at 5". Because the screen is so huge, they shrunk the buttons on the side. Of course it has dual analog sticks! but I haven't really used them in a game yet. (Damn I should have bought Peace Walker digitally!)
The Interface is nice, but there is no button support in the main menus so you have to use the touch screen.
Right now I have Uncharted: Golden Abyss and Hot Shots Golf: World Invitational. I've only played HSG and it is fantastic - about the same as all the other HSG games but it plays very smoothly and the graphics are quite impressive. My cousin played Uncharted on it and was having a blast. I'm definitely going to buy the new Lumines when I see a good deal.
1. No PS1 support yet
2.There isn't full PSP digital support
3. Sony chose not to bring the UMD Passport program to NA or Europe
4. The battery life - most of what I have seen in articles is 4-5 hours playing games. (So far I've just drained the battery once and I'm not sure what the time was. My best guess would be at least 5 hours)
5. I can't plug the system in the PC and easily transfer files, you have to use the interface on the vita and it is pretty tedious.
The best thing is I got the system and the two games for less than $200 with discounts =D. If ya have any questions about it then I can do my best to answer.