It's an exaggeration. I seriously doubt Microsoft would fire their employees for not using Microsoft technology, but I would also see the phones as serious dog-fooding. Microsoft needs to know what's wrong with windows mobile that makes nobody want it and it's obvious whatever they had been doing prior to w7p wasn't working at all. What w7p will become is unknown and its success is far from sure. It's more likely market share will keep eroding, undermining their desktop market share even further.