"what ever sales boost 360 gets from halo 3, The wii will get a bigger boost from Mario Galaxy, Smash bros and Metroid."
I doubt it for two reasons:
Metroid as the first two prime games didn't sell as well as Halo (although I am hoping the control scheme changes things in the same way that Halo's control scheme set the console world on fire).
Two of those games release after the Halo 3 release week so they won't affect whether Halo 3 gives the lead back to the 360. Also I should precise that I believe that if the 360 gets the lead back this year either from Halo 3 or christmas it would only be temporary with the Wii retaking it for good in 2008 (if it concedes it at all that is).
Also, I did not take MP3 in account because I did not have time take in account the 360 games coming out in the coming 5 weeks so it would not be fair to take MP3 in account.
Another thing I wonder about is with Bioshock's excellent reviews and ensuing hype, will it move hardware a lot? Will it move hardware enough to give the 360 the lead back next week? It seems unlikely as it would have to more than double worldwide 360 sales which is a tall order for a new franchise. For comparison, the 360 did similar to the Xbox christmas periods (500k in november, 1-1.1 millions in december) with the hyper hyped Gears of War so I do not believe that Bioshock can do it.
"I do not suffer from insanity, I enjoy every minute of it"
