Don't get an SV650. My buddy has one, and it's really not that great of a bike. My other buddy's 86 honda interceptor is faster, lighter, has smoother power delivery, and gets better gas mileage, and it's 20 years older...
Plus no matter what you do, the SV650 will never sound real good with that 2 cylinder in it. I'm not really sure what the appeal of this bike is to anybody, in my opinion it doesn't even look that good because of the rear fender.
So it's just my 10 cents, but if you're going to go out and buy a bike that new, get something with a 4 cylinder in it.
Anyways, I've wanted to get a bike for years, but it hasn't happened yet. I really want a RZ350 because they're so different from any other sportbike out there, but they probably get worse gas mileage than my car does, because they're a 2 stroke.
I wasn't really planning on getting a superbike either, but for the last couple months i've really been eying up a triumph T-595 thats for sale at the local powersports shop. Probably not that great of a choice for a first bike though but I really want it and they're only asking $4,500 for it.