It is a pretty well known that the telecoms are struggling to find an identity on the internet. Most of the big internet companies like Yahoo and Google are using the existing structure to freely build applications while the telecomms struggle to support the infrastructure.
Typically the internet applications have very little direct impact on the phone companies other than to create more traffice. However, Google has fired a direct shot right at them with Google Voice.
http://google.com/voice --Some people may already be familar with this service as the old Google Grand Central.
You sort of knew this time was coming I just didn't think it would happen now. Google has now inserted themselves in the relationship between a customer and their phone service. Google voice is an enhancement of a large number of features that typically represent pure profit for a phone company. Plus throw in the ability to send and recieve SMS messages. Then add the new ability to see the history of the messages, block callers based on identity, route calls, transform voice messages to text, record calls, and listen in on messages that are being left all with your existing devices and numbers. That is a great list of features all for the incredible price of free. Even if this doesn't become wildly popular it should force even the VOIP providers to push their offerings to the next level.
As a traditional telecom with very little functionality on the web today Google is raising the bar and creating barriers for entry for the telecoms to compete against. The ultimate fear for the telecoms is that devices, and other technology companies margenilize their offerings so they become simply a provider of pipe space. I think with Google Voice the fear is one step closer to reality.