Worldwide most likely, the United States possibly, but I think unlikely before a new XBox is launched due to the headstart (Microsoft will probably want to 'declare victory' here and say a new gen of consoles started). I think the PS3 may well outsell the next XBox as well as the current XBox.
I don't think in gens based on release dates, but rather based on technology. From that perspective the Wii is last gen and the 360 could be viewed as a product in between console gens compared to the PS3.







