Microsoft has publicly come out and announced its interest in shutting down CSF, which is a blow to the Voice 2.0 (supposedly a new market was emerging according to the VoIP guru's). Given this impact and the lack of focus of the SDP platform for the telecomm clients. Did the telecomm guys actually need Microsoft to teach them how this whole telephony business works out? Hardly! The direction of getting telephony over the IP networks makes sense and having some innovative applications integrated with the VoIP based platform also makes sense, but having every application being integrated is a far out-cry.
Your truely was involved in the efforts of building out components of VoIP that could integrate with Microsoft's CSF and HMC 4.0 (I was not a Microsoft employee and worked for a VoIP software startup a year ago.). The business had some needs and market requirements but needed to be architected and addressed properly. Things do fall apart when people start policies of selling ice to eskimos.
That being said the NGN and IMS will work within enterprises but they need a serious hair cut. The efforts of NGN is a good one, but having studied it well and looking at the potentials, we do need to trim it down and bring it to the applications of the enterprise. Also, the market for NGN needs to add applications and software players involved in a bigger way. Businesses are not going to but from the telco's. So companies like Microsoft will play a role, although in moderation.