The whole suggestion that the next xbox is coming out in two years is not only silly, but is also directly contradicted by the statements from Microsoft's CFO yesterday (the infamous 100M units statement).
CFO's don't lie because they go to jail when they do.
So we may doubt that the 360 will actually reach this milestone. But we should not doubt that Microsoft is going to planning to make a real run at trying to get there. So we should take the statement as "We are planning to push the 360 hard with the hope of getting to 100M units sold".
This kind of statement also means that there are no plans to stop pushing the 360 for the foreseeable future. The plausible way for Microsoft to get to 100M would be:
EOY 2009: 40M
EOY 2010: 55M (priced at $200 for the slim 60GB model)
EOY 2011: 70M
EOY 2012: 85M (priced at $120 for the whole year, introducing the next xbox)
EOY 2013: 93M (selling side to side with the new xbox)
EOY 2014: 98M (priced at $99 selling side to side with the new xbox)
EOY 2015: 103M - last holiday season
Based on this roadmap I would expect a new Xbox not earlier than EOY 2012 - 4 years from now.
Prediction made on 11/1/2008:
Q4 2008: 27M xbox LTD, 20M PS3 LTD . 2009 sales: 11M xbox, 9M PS3







