Well WolF Bird you will have pardon my disposition because you know I'm always eager to encourage people to buy stuff

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If you are concerned about battery life then definitely get the slim. The screen may not be as good, but you will more than likely not notice. They did a similar thing with the PSP 2000 and the PSP 3000. The PSP 3000 had a cheaper screen than the 2000 did, and I was used to playing on the 2000. So when I got my 3000 I was able to tell the difference, but after a while it didn't bother me at all. In fact I ended up getting rid of my 2000 and keeping my 3000.
One thing to know about Vita slims, is that they are currently only available in the Borderlands 2 bundle. Sony has not announced when they will be available to purchase by themselves. Maybe they will say something about it at E3. Another nice thing about the Borderlands 2 bundle is that it comes with an 8 gig memory card too. Something that you will have to pay extra for if you wait to buy the Vita separately.
I think your best bet would be to get the Borderlands 2 bundle and just not download the game if you don't want to play it. Then you could get it sooner, and get the memory card as well. You could also wait to see when the Vita slims will be available by themselves, but Sony has made no mention of it as far as I know.
For me, the original Vita is fine because battery life is not a problem since I don't ever take my portable systems out of my house to play them. My portable systems are simply extensions of my gaming library. I will just sit on my couch and play them if I want to. I've never used any of the PS3 connection functionality, so I can't comment on those features, but as a portable gaming device I like it a lot.