Who has an invite and wants to be nice and send me one? From what I've seen it seems like a cool idea. For those who haven't seen/heard of it: http://www.google.com/googlevoice/about.html
Just sign up. about 2-3 days later you'll get an invite if you leave your email addy. I have 3-4 google voice numbers. don't use them though. try to see if your cell phone number is available in another area code...pretty useful actually.
i don't think it will catch on to be honest unless they try to get skype or another existing platform