To be honest I don't see why the short term boost matters much. Basicly there are Xbox people and everyone else. Xbox people love FPS games, are almost exclusively male and 18-34 and love online trash talking. They love the Xbox and love the 360, and will buy the hardcore gamerboy machines until MS stops making them. The downside, of course, is that there are only about 30 million of those xbox gamerboy types which is why sales have shifted continually downward for the 360 even with price drops. There is an upper limit of about 30 million for 360 sales just like Xbox sales, and MS CAN speed up how fast that 30 million buys an Xbox but is going to have a really hard time raising that at all.
Ask anyone who isn't in the Xbox demo about the system, they have 0 interest and probably never will. The everyone else demo will buy a PS system (they certainly bought the PS1 and still are buying the PS2, you think its hardcore gamers giving the PS2 a half million in sales each week?) and will buy a Nintendo system (as evidenced by the Wii) but I seriously doubt any of them will be talked into a 360 any time soon.
The other problem for the 360 is a lot of the gamer demo also has a gaming quality PC which further stunts Xbox demand. Even Xbox exclusives are 90% of the time on the PC in superior versions (extra features for Mass Effect, Gears of War and others after a PC port) which means that the only gamers who really need a 360 (and are willing to settle for the inferior controller vs keyboard/mouse) are those who can't afford a gaming quality PC or don't want one for some reason. I haven't used my 360 in at least a year because of that strong increase in superior PC ports (or even PS3 ports) of all the good 360 games except for a few hours of disappointment with NG2 as a rental (the first time since Devil May Cry 2 that the sequel has been inferior to the original). I wouldn't even have one now if Macs had been able to use Windows (for games) back when the 360 was released.
