GrandCentral is forced to change about 400 user phone numbers due to an issue with one of the phone carriers. The customers affected will have to start using the new phone numbers by Aug 30, 2007.

<< The numbers had to be changed after a "local carrier partner" recently notified Google it would stop its service and thus would be unable to connect calls to the GrandCentral numbers issued in its coverage area.

"We worked around the clock to transfer the majority of numbers affected by this to another partner, but this process didn't work for some – about 400 numbers," a Google spokeswoman wrote via e-mail. She declined to name the carrier and the affected coverage area. >>

http://www.pcworld.com/article/id,136202-c,webservices/article.html

I wonder how many thousands of business cards will have to be reprinted because of the new phone numbers.

GrandCentral has responded on their blog...
http://blog.grandcentral.com/?p=137

What happened to number portability?