Judging WP7 on WM past might be a huge mistake. It's a new beginning, with lessons learned from the Symbian, iOS, and Android experience. A few years back Microsoft fired the previous WM managers for gross neglect, hired hundreds of new people from outside, and developed WP7 from scratch. It's entirely new from the kernel up. Also, not a huge amount is known about the internals - for example (hundreds of speculative articles notwithstanding), we still don't know the true architecture wrt multithreading and multitasking. Also, MS is really making a serious effort to bone up quality all round ... Expression Web pipped Dreamweaver to everyone's shock and surprise, then W7 largely fixed the Vista fiasco ... IE9 is very promising, the new servers are stunning performers. They're coming from way behind, they know it, and that's what brings the best out of the company, which was once must loved by PC fans, believe it or not.
We do know with WP7 MS is playing for the long haul, with sights set on a 3-4 year horizon sweet spot, as steveb has often said. They're also very conscious not to make the same mistake as WinCE/WM, where the hardware capabilities and performance price-points eventually outran the original design paradigm, ie WP7 is architected for not just today's high-end devices but also for 5 and 10 years down the road.
I've been a long-time WM user, but I remain cautious. I'm not into youtwitface social networking and gaming, which gets a heavy emphasis in this first release of WP7. But millions are, and by most accounts MS is doing something really new with WP7. Whichever way it pans out, we're in for exciting times. My only tip is: take off fanboi blinkers, develop a healthy skepticism about brands, and pick what works for you. It's only a tool, after all, not a value system. I'm rather contrarian and tend be put off by herd brands, if only to avoid the herd.
