[grimm]

Broken,
From what i understand the D40 is not an Auto focus body, you need to get lenses with the auto focus in them. (please correct me if I'm wrong) i think it is also a cropped sensor body. Like the canon xt, xti.

if i were you i would go to store and hold a canon and then a nikon and see what is more comfortable for you. The benefit of a canon body for you is that the menu functions and interface are going to be more familiar since you have a Canon Point and Shoot. I personally had trouble finding things thru the nikons menu, but that because i've used a canon for years.

over all i think and this is just an opinion. canon is a tad sharper, nikon has much better High ISO.

depending on how far you imagine yourself going the next important thing to think about is lenses. The quality of each are pretty comparable, but some of the nikkor glass is harder to come by. but again that might not ever become a problem for you if you aren't ever going to spend over $1k on a lens. Other than that i would say it's all personal preference.

I went from a canon G5, to a rebel xt, to my 40d. I also own a Canon SD750 point and shoot.