Whats the last game you've bought? First say the last retail title then the last downloadable title.
For me
Retail:Uncharted
Download: Fat princess
PLAYSTATION®3 is the future.....NOW.......B_E_L_I_E_V_E
Consoles owned: Game Cube, Gameboy Color, Gameboy Advance, Nintendo DS, PSP, PS1, PS2, PS3.
My prediction: NATAL WILL NOT help 360 sales. Maybe a 50-100k boost week 1, then a 30-70 k boost week 2, and back to the norm again after 3-5 weeks.