Not really, D90 is cheaper than both, but straight from camera files have less noise than those from 50D/D300. However, if you know how to post-process noise, it's hardly an issue, with any DSLR body available on market today.
You should go for d300s....... unless you're buying 2nd hand.
Anyway, for me, i chose nikon cause of the interface and body feel. Canon just dosn't suit my hands and i just cant get used to using the interface from canon.
If you have lobang, you can rent both cameras and try them out for a day, if not just go to john 3:16 and try them out on a weekday when its not so crowded.
