Until very recently Canon had the edge over Nikon with their DSLR range, especially at the higher end, but now they are pretty much on a parity. The one thing they both have in common is that the 'Kit' lenses they offer aren't very good, so I would be tempted to go to a camera centre rather than Argos or amazon and try and negotiate for a lens upgrade rather than get lumbered with something that'll give you mediocre results right out of the box. In the end, the camera is the box that records what the lens captures. It's all about the bit of glass on the front of it.
I bought a canon 550d when I was in new York last nov. got a good deal on the kit lens and a 300mm lens. I soon upgraded to a 50mm prime 1.8 ( fab for the money, but plastic fantastic), a 28-75mm Tamron 2.8 ( better value than the canon equivalent)and a canon 70-200mm 2.8L. Lenses make the biggest difference in quality and speed, and fast focusing. Although the kit lens is very good, the autofocus speed is average. No good for fast moving objects, but portraiture is fab quality. I was umming an arring between the 550d and the 7d, but the 550d shares the same sensor, mp etc.. The 7d has more fps burst though, and is bigger and built better. Not worth the extra IMO, but that's my choice. I would rather spend on better glass. Both are cropped sensors. I would love to go full frame in future, hence the new glass, and it fit on full frame. It ain't the camera that takes the pictures, its the skill and eye that does.
I use cannon 40d and love it, some right deals on ebay too.. mine cost a pack prob two years ago but have seen the super cheap on ebay. Posted on my HTC Sensation with Tapatalk