MY CURRENT TOP 10:
OK, #1, ability to install Windows.
#3, Better PlayStation Home, and PlayStation Store
#4, Backward Compatibility with PS1, PS2, and PS3
#5, More USB Ports and Firewire (U USB, 2 Firewire would be helpful)
#6, Bigger HDD, namely a 7200RPM 500GB, or more
#7, comes with a keyboard, mouse, headset, and HDMI/ Component Cable
#8, cheaper than the PS3 was, if possible
#9, more RAM (PS3 only has 512MB)
#10, Flight Simulator
P.S., did you notice there was no #2?
#2, Ability to play MP4 Movies, and a Better Internet Browser