I was a Canon lover before I got my first DSLR which is a Nikon D40 (which has been replaced with the D3000.) The reason I went with Nikon was lenses. Nikon uses a standard lens locking mechanism that allows almost any lens to be used on the body. Not so with Canon, which is *fine* if you plan on only using Canon lenses.
I wanted variety with my lenses, especially since I have access to about 5 really amazing lenses that are old regular SLR lenses... which still work with my Nikon, I just don't get the auto focus feature... not a big deal for me, so Nikon it was!
Both of those cameras are about the same all the way around. In my mind the lens issue was the only deciding factor for me, although the Nikon did slightly better in an ISO test (as shown on Ken Rockwells site, which I've linked at the end.) Both cameras are coming with more or less the same lens, 18-55 mm with the same f-stop range. Its a good beginner lens, but it can't do a lot of macro or distance photography. Don't expect to get awesome bokeh with that lens. :/ Anyway, they're probably going to take the same shots so its up to personal preference. If there's a camera shop near by go hold them, that can also be a factor. Mine has a slightly smaller body with jammed together buttons, which I LIKE. Some people don't. Check out Ken Rockwell's reviews, he shows the back and top of the camera so you can get an idea of what he body will look like.
While I'm not certain of your price range, I will add that 10-15 mega pixels is sort of overkill, unless you intend to blow up the pictures to the size of a wall. A large wall. More mega pixels wont make your photos better, having better photography skills will make your photos better. Just something to consider. You could spend less on the camera+lens kit and buy an extra lens, say a 18-200mm or a 35mm (f/1.

if you want to do more close ups. It really depends on what you want to shoot. But 6 mega pixels is more than enough for great 12x18" prints. If you plan on printing larger than that-- then consider going up in mega pixels.
If you have any other photography questions please feel free to ask. I did a lot of research before I bought my camera, but like I said, it was ultimately up to personal preference as far as which brand to go with.
A good review site from an unbiased guy... he isn't funded by anyone, so he doesn't pick favorites based on manufacturer.
http://www.kenrockwell.com/And this is also a good resources for basic photography. Even if you
know basic photography, she uses really good examples to explain things like ISO, shutter speed and aperture.
http://thepioneerwoman.com/photography/ ... /exposure/