Let me also suggest that you get your news and information about Google Voice/Talk/Chat/Hangouts from the official Google Product Forums (GPF), instead of from a highly-opinionated (and at this point, ranting) blogger (Ward Mundy). He's attempting to twist Google's business and technical direction into some sort of devious and dishonest scheme. "The lady doth protest too much, methinks."
The "Android Community" blog was also inaccurate: "This all centers around Google's move away from XMPP, the protocol apps like GrooVe IP were using to latch onto Voice. When Google went from Talk to Hangouts, they transitioned away from XMPP, making things like voice and video chat proprietary. Google is now bringing that energy to Voice, opting to shut down operability with no alternative in sight."
The "alternative in sight" is already here: Hangouts. Hangouts can be a forwarding VoIP phone destination for GV calls. Hangouts can dial telephone calls. Google Voice never inter-operated with XMPP. Google Chat did, and Chat is being replaced by Hangouts, which will migrate to communications via WebRTC and HTML5. Focusing on WebRTC allows the browser to take over functions that formerly required a plugin. That plugin is a messy kludge, and every time it gets updated, it manages to break people's calling from Gmail. The latest plugin update broke calling for a lot of Mac users, for example.
The main point of confusion, is that Google Voice is not, and never was, a free phone service. It's an inbound call management system. Google's companion products, Talk, Chat, and now Hangouts, provide the VoIP functions. Yes, the names are confusing, but the important fact is that Google Voice isn't being shut down. Over time, we expect that most of the GV functions will be better-unified with Hangouts (both on the desktop web browser and the mobile interfaces). The GV team is working on this, but getting it right, without breaking the complex GV infrastructure, or pissing off the millions (yes millions) of GV users, is the top priority.
These blog articles are not helping people understand their options. As gderf points out, you can still use Google Voice with your OBi; just not with the Chat pseudo-phone via XMPP, that OBi and GrooVe IP have been using. And, as he pointed out, there are several other threads where you can read about these options. Enjoy using GV with your OBi!