Skype not routing incoming calls.
 

Don't know if they still aren't, but it seems that on Friday SkyPE were having massive problems routing calls via their SkyPEin service..

http://www.theregister.co.uk/2006/11/03/skypein_down/

Now, this makes me wonder if they are actually ready for large scale use. AFAIK, none of the major non-voip telecoms providers (BT, NTL etc) have ever had an outage that prevents most of their customers recieving incoming calls, and if they did, there would be outrage.