The most interesting part of this interview with Horace of Asymco about the Surface is his take on the difference between how Apple and Microsoft view tablets:
I have some guesses but I don’t think it’s something that is defensible. Too many things can change. Fundamentally I believe Microsoft sees the tablet as a PC and intends to migrate a substantial portion of would-be PC customers to tablet forms. If they are successful then they preserve the existing PC user base and allow it to grow a bit.
In contrast Apple sees the iPad as a new type of device that is used for things not directly related to PC style computing. In that sense the iPad competes with PC non-consumption. It means people may own both a PC and an iPad and some will own only an iPad. The iPad will expand the market while taking share from the PC. Windows tablets will try to hold the Windows share steady.