This post by Rich isn't really new news. It's been documented before that Skype poses risks inside the Enterprise via the way it punches a hole in the firewall, and also now with it's API.
One would think one of the first things the folks at eBay would do is attack this issue, but eBay is very corporate from the top down, while Skype is very radical in the way they work. But so far, other than some report that didn't tackle the problem, and a weak effort to tell that story, Skype really hasn't cured the perception or the reality.
Rich's post today clearly points both those facts out.
Skype has a security resource center that helps explain things.