I have an upcoming 2 week trip with lots of travel and was considering buying a Vita for some NES, SNES, Genesis and Sega CD emulation action. I already have a PSP which can do this but I really like that Vita screen.

I really haven't been following the homebrew scene for any console for over a year now. Is this possible on PS Vita as of yet? If not I guess I'll stick to the PSP.

Not yet, but there was an article not too long ago that someone figured out how to hack the Vita. If it is true, it will probably be a few months until the first batch of homebrew goods come out.

Bah...I need this in 3 weeks. I guess I'll get one of those android based handheld emulators... or see if my PSP still works lol.

I'm not the most informed person on this matter, but I was under the impression that PSP homebrew already worked on the Vita, it's just that there is nothing that takes advantage of the Vita's hardware yet. If that's true, classic system emulators should work fine. Once again though, I don't really know.