Android phone owners will soon be able to video chat with each other using Google Talk over WiFi, 3G or 4G networks, Google announced in a blog post this afternoon. The feature will roll out first to Nexus S phone owners over the coming weeks and to Android 2.3 (Gingerbread) and newer devices "in the future." It's a start!

The offering, when it ships, sounds like it will be more compelling than Apple's Facetime but less useful than independent mobile video chat apps like Tango that offer iPhone to Android video chat. A number of mobile video chat apps have been launched in just the past few weeks from Skype, Qik, Fring (now with group video calling on iPhone!) and others. But how long will we have to wait until Android users can video call iPhone owners without any more thought than voice calls require today?

Why all this video chat going live now? Tech blog VentureBeat ran a guest post earlier this month from Rebtel CEO Andreas Bernstrom about why now is the time for mobile video chat to take off. Bernstrom argues it's because of four factors: social networking, improved call quality, increasingly common cross-device compatibility thanks to software and the network effect of exploding sales of mobile devices with front-facing cameras.

From dreams of remote medicine to already deployed high-end hotel concierge consultations, video chat has a lot of potential in a lot of different circumstances.

That potential, though, is hobbled by the contemporary equivalent of an inability for customers of two different telephone companies to call each other by voice or different trains to make it across the whole country over different rail line company tracks.

Where's the Open Technology Standard?

When Apple launched Facetime a year ago June, Steve Jobs said it was going to become an open, universal technical standard. We haven't seen that happen though, or at least we haven't seen much development on top of it. Might Google try to accomplish that big picture goal to go post-silo in mobile video chat?

Will the Google Talk implementation be as well executed as Apple's is? Will it be available anytime soon for iPhone and thus be at least that close to cross-platform? Will we someday be able to video chat from one phone to another regardless of its maker or OS, as easily as we can do voice calls today? Presuming that's something people really want beyond the initial wow factor (and to be honest, I'm not sure it is) then those will be big questions to watch for answers to.