Does it really matter that they're using an open video codec when their protocol itself is not? It's at least of little utility to anyone else that they use an open video codec.
Skype has been using the VPx codecs for as long as they have done video calling. if VP7 was good enough for them, there's no reason why the new and improved VP8 wouldn't be. they aren't moving to any new technology here, nor are they embracing VP8 because it's open. they are merely upgrading to the latest version of the same codec they have always used.
It matters now that they've been bought by Microsoft, and are switching to anything other than a MS codec. It's news because maybe MS is warming to the idea of using existing open standards in places where it makes more sense than their own.
