You really cant go wrong with either the Nikon or the Canon's, both are comparibly capable, though more of the so-called pro's who do this sort of thing for a living tend to go with Canon.
I went with the safe Canon 40D with same make lenses 18-55, 50mm, 75-300.
Im an amateur by jimmys standard and he's got one heck of kit
but im sure even he'll agree that, lenses are just as or more important than the chassis itself. Dont get me wrong, you still need a good/sound chassis but lenses are what captures the images and how well its reproduced.