I have a Canon since the Michigan Reunion and love it. I bought the Canon based on the lenes and price. I started with a 20D and now have a 5DMarkII. My main concern was a fast IS lens,2.8.
Current lens of choice is a 70-200 2.8 and I recently purchased a shorter 2.8 zoom for portraits and moving grandchild. I sat in the audience at a dance recital and videod a 4 minute performance in HD digital with the 70-200 zoom lens w/o autofocus and hand held. I think it's network quality.

Both brands great - make a list of your priorities, and check your options. If your buying any lenses , make sure they are compatible if you upgrade your camera body in the future.