IIRC @ WPC Andy Lees clearly said that in the future version of WM (he didn't obviously name it WM7) updates will be directly provided to the user by MS and not the network providers anymore (just like the iPhone) and said that more info about the next WM will be released at PDC in October.
Can't find the keynote video on Microsoft's site anymore (and strangely the interesting parts have been cut out of the transcript, mainly the Q&A IIRC..
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