A senior executive leaving Microsoft may not always be the best of signs for the company and / or the exec, but it appears that Charlie Kindel's just-announced departure is an amicable one for all involved. Kindel, as you may be aware, has been with Microsoft for 21 years, and most recently served as general manager for the Windows Phone Developer Ecosystem following earlier terms leading up the Windows Home Server and eHome divisions. So why pack up and leave all of a sudden? It seems Kindel has decided it was an opportune time to launch his own startup, which he's keeping suitably mysterious at the moment (something to do with "sports, advertising, mobile, social-networking, and, of course, the cloud," apparently). He has decidedly more to say about Windows Phone, however, which he calls flat-out "the BEST product Microsoft has ever built" (emphasis his), and one that he won't stop using after he leaves the company. Hit the links below for Kindel's own message announcing his departure, plus an interview with GeekWire.