I agree with Madelyn; it's all about preference. I myself am a Nikon DSLR user and I just prefer it to Canon for a few reasons, MOSTLY that Nikon seems to handle Digital Infrared Photography better than Canon does.

But really, I would just try both out. I've heard that Canon can sometimes be easier for a beginner, but I started on a Nikon and had a great time learning on it. I would just get the simplest DLSR model you can, and then move up if you feel like you're not getting what you need out of it. Try them both out at the photo store and see what you prefer!