Lieutenant Commander Nelson let flow the mango-kiwi juice of information on the Xbox Live Vision camera release date in his latest podcast. The firm, yet loving date: September 19th, 2006 AD.
He didn't say how much it would cost, but the Xbox 360 gesture recognition depends on two the Xbox Live Visions, so they shouldn't be prohibitively expensive.
Other aspects we're looking forward to: putting your face into characters in games (hasn't been announced but there's been talk forever), and using your face as your gamerpic. We hope there's some filtering on that, or else there's going to be a lot of hairy testicle gamerpics on Live.