I was curious and read about the Windows phone platform (even though the M$ OS on the Samsung Jack was the worst I'd ever owned) and found a concensus that if you owned a Zune HD Touch (which I do) then you had a pretty good introduction to the Windows phone.
Well, I hate the interface of the Zune Touch.
I wouldn't bet on the Windows phone platform being around in the long term, my money's on Android- and the iPhone will linger for those too independent and creative to consider anything else.