Groove, I'm not sure of your level so I'm going to assume less knowledge, not more. Hope that's okay!
WRT the Nikon. Okay, you can go higher or go to another comparable brand - the only one is Canon. IMO if you like the Nikon (or Canon) but maybe want to get a Pentax/Sony/Olympus, then don't bother looking at the Canon (or Nikon).
The reason is simple: Canon and Nikon are equivalent technologically. The other three have one fundamentally different philosophy: anti-shake is built into the bodies so you don't have to buy expensive anti-shake/VR/IS lenses. It is not perfect but IMO the best trade-off.
WRT your comments on the Sony: more megapixels are meaningless at your level. Nice to have, though, and don't knock them back. Is low-light performance (i.e. high ISO) very important to you? Anti-shake can alleviate that problem but only for static subjects. How does the Nikon's high ISO performance look compared to the Sony's?
Check DPReview to compare:
http://www.dpreview.com/reviews/sonydslra200/page17.asp
Lenses: for goodness sakes, man, you should know that most zooms suck. Expensive zooms are usually as good as the price tag implies. I will make a quick recommendation based on other people's testimonies: Tokina 12-24 f/4.0 for wide angle and whatever primes you can get for telephoto. A good zoom (preferably constant aperture) is a good thing to have, too, if you don't want a bunch of primes in your bag).
FWIW I like Nikons. I also have confidence that Sony is serious about the DSLR market. Canons are great - I just don't care for them in the slightest (but I love their video cameras). Pentax and Olympus worth looking at, too.