1mil seems to be the achievement of most games. Anything higher is a bonus.
(I don't apply this to mario games or gta. Games like these need to hit at least 5 mil to get a sequel imo.)
Damn things have changed since 2009 began. Here are my new visions for the end of the generation.
Wii: 135 mil
Ps3: 85 mil
360: 60 mil