Personally I am using D90. But 50D is also very good. I encountered same issue picking up between d90 and 50d.
What I did is:
1. Go to the shop, compare the two camera head to head.
2. Feel both camera in my hand.
3. See what are the things I can get between the two models within my 2k++ budget.
4. Make sure that you will be happy with your decision.
5. End up getting d90 + 18-105mm vr + sb600 + lowepro bag + 8+4 gig card + UV Filter + Tripod + Re-chargeable Batt for Flash + Card Reader.
Now, no regret with my decision, just got battery grip + orig batt + Nikon padded strap last week. Coming soon AF 50mm 1.8 D. BBB Virus now with me waahhh...:cry: Soon my wife will throw me and my camera set outside the room Lolz...:bsmilie: