D90 definately have an edge over 500D
not because i'm a Nikon user but by comparisons,
functions, ergonomics, and every aspects...
please use DP reviews to look at the side to side comparison and you will understand why.
try to search, compare and read up on your own.
whats positive for me may look negative for you
Same here, like 450D but doesn't feel good for my right hand, now looking at D90 too. Already hold it and feel the weight and ergo fits nicely. I'm waiting for D5000 launch and hope D90 price will dip a little.