IMHO you can't go wrong with Canon, I've been using their stuff for the last 15 years and always been chuffed with the reults. My camera body is the 400D at the mo but would really like to upgrade to a full frame EOS 5D. The only real issue I have is that my lens's don't have image stabilisation so to avoid camera shake when shooting action stuff like motorsport or aircraft, I've got to use a fairly fast shutter speed and risk freezing background/wheels or props on aircraft/helos etc. It's always a fine balancing act but I love the challenge really

I've a gallery with some stuff shot with my 400D here
http://jalbum.net/browse/user/album/374266/5d was out of my price range as I needed some new lenses also, 5d Is s a nice beast though maybe in a few more years Ill get a full frame. My new lenses have the image stabilisation and its spot on for the sports / motor racing stuff. When i switch to my older 400mm lens the shake is terrible and I defo need a monopod to get anything half decent.
BTW the photo's of mine above are so noisy because Ive shrunk them down to upload, honest.