This is want I want in my new phone:

All that N900 has +:
NFC
Faster/Newer Hardware!
Longer battery time
Android App's compatibility/Emulation
Voice phone operation (or what ever is called)
Good front camera for Video calls
Thinner

N900 has it alredy, but a absolute must have is:
Physical keyboard
Phone support (3/4G)
SMS
GPS
Wifi
Bluetooth
Memorycard
VoIP and Skype integration
USB port (some mini ones)
User remoavable battery

/Mami