"At the moment Microsoft is making comparatively minor inroads into the telephony market with Windows Mobile 2003, in both Pocket PC Phone Edition and Smartphone iterations. Such devices include the xdaII / mdaII / i-Mate etc and SPVs. The maker of all of these is a company called HTC, an OEM from the Far East that may be unknown to the majority of the users of its phones which are sold with carrier branding by the likes of Orange and o2 in the UK. I think what was needed was a major, consumer-known, phone manufacturer to get behind Microsoft to force carriers to bring MS-based OS smartphones to market."
Source:
Neowin