Mozilla puts Firefox development for Windows Mobile and Windows Phone 7 on hold
The reason for this is that Microsoft “decided to close off development to native applications” for Windows Phone 7 Series.
Of course, Mozilla could continue developing Firefox for Windows Mobile 6 / 6.5, but, as Skype also knows it, supporting a dying platform is pretty much useless.
Anyway, if you have a Windows Mobile 6 phone and want to test an Alpha version of Mozilla Firefox (Fennec), you can still download it here. But if you want a mainstream mobile OS that will get a final version of Firefox this year, look no further than Android. Or, if you have a Nokia N900, you can already enjoy a final build of Firefox for Maemo.