Here's your three month notice.
Objectively, I can say that this is a negative simply because Windows Live/MSN Messenger and Skype never really competed with one another. MSN Messenger sees most of its utility as an IM client, while Skype is a video stream. They're different services, and axing one to force others to use another (the Google way!) doesn't really help Skype users out or enhance that service's experience.
More relevant to AP, I know MSN is extensively used abroad, with most of its users coming through international spheres. I still use AIM as my primary contact service, but I've connected to almost everyone I know on AP through MSN because of its versatility.
In the end, I'm disappointed Microsoft feels IM is obsolete technology. Chat clients like IRC are still popular around the world and stand testament to otherwise.
lol Web 2.0