i don't think that MS needs a price drop right now: on WW weekly basis it's still on par with ps3 (10k more or less is not significative) and i think that this situation is gonna remain the same during this holiday season...and the gap is still of about 7 millions console (actually more than what PS3 has been able to sell till now).
If you ask me i think that X360 will be in need of a price drop the price only AFTER this holiday season (i imagine right before the launch of GTA4)
As for "disappointing Mass effect sales" i think you should consider that in most EU ME went on sale on the 23rd...and at least before considering Mass effect a flop i'd wait for US numbers: i bet that 2 millions WW LTD is still at reach/possible (not bad for a new IP, is it?).
44.2 M 
27.1 M 
20.8 M
