Agreed, there is little chance Microsoft will allow another "XP" again where it competes against its own newer products. Windows Longhorn (Vista) was to arrive in 2003, instead we got it in 2007 and it was basically a test product for Windows Blackcomb/Vienna (7) in 2009. Far too long of a wait, companies are reluctant to switch because "if it ain't broke don't fix it" and the comfort level of a heavily refined Windows eXPerience.
Expect Windows 8 pre-releases and betas throughout 2011 & 2012, and Microsoft might use it as big test for Windows 9 in the process.
