I am not really a religious zealot of operating system in mobile gadgets, but much more to its quality, for sure.
I have had my HTC 8125 cellphone for about 2 years now and the longer I have it the more frustation I've experienced due to its lousy Windows mobile 5.0 O/S. For example, it gets slower and slower if I open multiple applications (why don't they put those applications running in the background in lower priority). Another thing is lack of its (free) development environment. Where you can find the latest development for free? sure you might get the free one provided, but it's gonna be 1 or2 generation older (for Mobile 4.0 or older).
Another thing is that everything is too tiny on the phone, unlike on iPhone which icons are made bigger and suitable for touch screen.
(to be continued...)