Bill...the D90 just came out and uses the same CMOS type sensor as the D300, plus it has a video mode that actually works fairly well. I had a D200 and recently moved to a D300 for the better sensor type. I tend to stay with the "pro" type bodies because they are more weather resistant, dust proof, built of magnesium alloy, etc, etc. The D90 is a great camera from all reviews I've been reading. And, their "kit" lenses are actually pretty good glass, though not in a "pro" shell. Nikon's 18-55 and 55-200 are tack sharp and not expensive. Another alternative lens that kind of does it all is the Nikon 18-200 DX with Vibration reduction....the VR even has an "active" mode which is meant to be used in a car or vehicle. It's practically the only lens you'd ever need, no matter what. Add the new Nikon 10-24 DX and you've got everything in the world covered, but you'll have $1600 invested in lenses with those two. If you want to shoot low light action shots, you're going to have to pay some bucks to move to something like a 70-200 2.8 DX VR...fantastic lens, but it's about $1800. The 18-200 goes for about $700. The other kit lenses I mentioned are the least expensive option, and they have some sharp glass in them, with excellent reviews by people who do this stuff for a living.
Also, Nikon has just released a D5000....you might want to check that one out as well...it'll be less expensive than the D90. Nothing against Canon at all, but I'm Nikon all the way. One reason for that is lenses they made back in the 60's will still work (though you lose some functions), but they will still mount and meter. Whatever you get, make sure the lens has Vibration Reduction (Nikon) or Image Stabilization (Canon) as it will allow you to get shots handheld that you normally would not be able to get without significant blur. The D90 has a FAST autofocus, so that's not going to be a problem. Like Don said, you can sink some serious money in this stuff, so think it through and choose what you think will cover the situations you find yourself in.
If you want a high end Point and Shoot type camera, take a look at the Canon G10...it has a lot of the functions of a DSLR and an equivalent lens of 28-140. It's built like a tank as well, and has control knobs instead of digging through menus to get where you want to be.
For some good advice, check out
www.kenrockwell.com He has a layman's writing style in reviewing equipment.
Check out my two websites for some images I've taken through the years with Nikon gear, and I'm just getting started with posting galleries.
www.terrycrainphotography.comwww.terrycrain.imagekind.com