TechCrunch recently posted this:
According to them, Google has now acquired Gizmo5. For those who don't know, Gizmo5 is a VoIP provider with clients for Windows, OS X, and Linux. Specifically, they run the only VoIP service supported by Google Voice, which is why this isn't so surprising. As of right now, the deal has not been announced officially by either company, but I'd suggest watching their blogs for more information.
So what does this mean for Google Voice users? Well, there are a few possibilities here. Google could integrate the Gizmo5 client's functionality into Google Talk, which I'd say is pretty likely. In the short term, they could stop charging for dialing out through Gizmo5/Google Voice... or they could keep charging, which would surely annoy a lot of people.
If they do keep charging, there's a nice little article over at Nerd Vittles that I saw a while ago. Basically, it describes how to integrate GV dial-out functionality with an Asterisk server. Take a look at it if you're interested.
Regardless of what happens, this move could serve to position Google as a formidable competitor to Skype. Consider this: Gizmo5's SIP services are open. Skype is completely proprietary. Gizmo5 is not very well-known. Plenty of people know about Skype, but even more people know about Google. The problem Google's had up until this point is that most people aren't even aware of Google Talk... which is pretty odd since Google is one of the largest advertising companies on the internet. If they actually start advertising these services, well, I think they could easily grab a huge portion of the VoIP market share.
Update: Google has announced it on their Google Voice blog.
On the Gizmo5 side, you don't need to look far to find this - it's on their homepage.