Stranger things have happened. That's for sure. But I'm not all that far toward buying Skype's "explanation", either. (Not that it matters to them what I think, in any event.)
Since this article went up, Skype has clarified their position that it was only the reboots that caused the problem and not the Microsoft updates at all. While I'm sure MS appreciates the pass of responsibility claims, the whole thing still reeks of implausibility. This article goes into that quite well and there is no need for me to repeat it here.
My personal suspicion(s) center on what seems a quick and easy explanations for the failure of a complex and ever-changing system.
P.S; I am NOT upset with Skype at all for the failure. Stuff happens. It just seems they could be a bit more forthcoming for their users' sake.