Whichever feels more comfortable to use; Nikon and Canon both make excellent cameras and lenses.
Nikon
Nikon all the way, bro.
canon
For me - it's Canon.
Nikon D60 Canon Rebel XSi Canon A590 Canon SD950 Nikon S51 Canon SD890 Canon SD790 Canon Sd770 Sony T200 Canon G9
Nikon here. Why?
I use a canon 7D and have seen that the clarity of a picture is same as taken on a Nikon D90. However, it depends upon how one looks at a camera and a photo taken from a photografer's point of view. To me canon is better than a nikon...
It depends on your preference. Canon is much more popular in the SLR space than Nikon, but Nikon users swear by their lenses.
Nikon cameras take better pictures.
Nikon, Canon.
i personally prefer nikon dslr camera, but for compact cameras in my opinion canon is better
Personally I think that Nikon is better than Canon, and it may be because I started out on a Nikon and have been on one ever since... but I truly believe that Nikon has a better quality and that it will last you much longer.