RHM has it pretty dead on. I have been a huge MS fanboy forever (even worked for them for a short while). For the last year I have been heavily investing in learning WPF and was extremely excited as to the potential, yet disappointed at the immaturity.
Yesterday I got my first Mac. After one day experience on the Mac as a multiple developer/engineer certified MS professional I am in shock how far behind windows is. I finally understand why Mac usage is on such a quick rise lately.
I know major projects take years at MS (at one time I was offered a sr position on the Win32 replacement team, 5 years later WPF was announced). If MS does not already have a major step beyond WPF in late development they can kiss their market lead goodbye.
I was semi interested in Windows 7, but after one day with a Mac I am not even going to bother.