Wait for E3 for sure. Everyone is anticipating a price cut and I highly believe that it'll happen then; also, the Vita will probably be getting a ton of new games and content at E3.
I own a Vita right now and I'm waiting for some better games. Great hardware, terrible software at this point. I would wait if I were you. I know it's a very attractive system and one that you're highly ancipitating getting, but trust me when I say that it's not all that it's hyped up to be. Until better games and apps come out for it, it'll be a shell of what it could be. Wait, you'll thank me later.