What could have been...
10. Region locked
9. No good Xbox Live Vision support. Sports games don't support it for create a player and no good Vision specific games.
8. No Xbox controller support
7. No built in Wi-fi
6. Discs can scratch, should have had Blu-ray type coating
5. No full backwards compatibility
(MvC2 is backwards compatible with the 360 but it is nearly unplayable due to Microsoft's shoddy emulation job)
4. Terrible D-pad
3. System gets extremely loud and hot
2. Xbox Live still costs money
1. Red Ring of Death
Even after all of this Xbox 360 still surpasses both the Wii and PS3 this generation IMHO. PS3 can't compete with the Xbox 360 in terms of software at this point. The Wii can't compete because it doesn't have the software I'm looking for, the online structure, or graphics.