Go to shops and play with them. See what feels best in your hand and have someone show you the different functions, one will feel much nicer than another. If it's not comfortable for you to hold and operate it you aren't going to use it much.
I have a Canon Rebel XT and a few Canon lenses and love it. I've had Canons forever so when I got my digital I stuck with Canon, didn't want to buy new lenses and start over with something else. I still occasionally bust out the old fashioned film cameras...my all time favorite to use is my Canon elan 7e. I so wish my XT had eye control, that is the cat's meow!!