The differences in graphics are subtle to me. From the gameplay features I've seen, stadiums and other field features look slightly more refined in Madden, while they seem to be about equal in player detail. I wouldn't take too much from those pictures, especially since one looks like a night game and the other is during day. If the game really successfully implemented hdr lighting, day and night pictures could be drastically different. But this is all very technical and it is a game, after all.
Really these games come down to preference. I just don't get the same excitement out of Madden that I do NCAA. That said, Madden seems to usually be better when it comes to the technical aspects of the game like blocking and running offense.