Many Skype users had problems making and receiving calls yesterday (NYTimes) due to a Skype software error.  The company has pinpointed the problem but is unsure why it brought down the network.

The company could not ensure that the phone service would be 100% reliable today.  The problem has been in existence for 4 years and is in every user’s software.  It took a unique set of events to trigger it.

Expect a software update soon.  =-)