There have been various IMS/almost-IMS video sharing trials and deployments over the past 18 months. Nokia's one with CSL in Hong Kong was an early example.
So quite why AT&T thinks it's somehow special is beyond me. Almost as far beyond me as why anyone else thinks that video sharing (or "see what I see" as some wince-inducing marketing people put it) satisfies any consumer needs whatsoever.
Leaving aside the fact that it doesn't work across networks, or on any but a handul of phones, or that people who are walking or driving can't watch inbound video, let's think about the practicalities.
1) I see something cool/interesting.
2) I call you up "Hey, I'm watching something cool/interesting, check this out!"
2b) 97% of the time you're on the wrong network, wrong phone, out of coverage or too busy to watch video
3) Miraculously, you watch what I can see, in realtime, over the network. Awesome!
4) I meet up with 10 other friends in the pub that evening "Hey, I saw something really cool/interesting today!" .... "Wow dude, did you record it?".... "Errrr. No. I expensively sent it to Eric in realtime, so I can't show it to you guys. Or upload it to Youtube. Or email it to my aunt. Damn".
And yes, I know the hypothetical scenarios of a business traveller being called by their spouse to see what their little child is up to. Given point (2b) above, this will only work on a call at a pre-scheduled time. When you might as well stick the little blighter in front of a PC & webcam and do it for free via Yahoo or Skype....
It's a solution looking for a problem.