Intel's Developer Services have published Geoff Koch's article on "Open Cell Phone Platforms". Open is a phrase that has been hijacked over the years by the GNU and FSF bunch, in this case it's a plea for transparency and control, which is why I'm rather smug I managed to get my comments into the final paragraphs.
It's a bit of a shame the rest of comments from the usenet thread didn't get included. It seems, to me, the phone platforms are limited by the needs of the carrier, not by the technology or by user requirements. Until that handcuff is broken we're not going to see any leaps and bounds in mobile phones. Neither Nokia or Microsoft will "win" the platform battle whilst the carriers enforce their limitations.