On another forum, I've read that one of the testers found the HDMI on the T4i to be clean. He recorded to an Atomos Ninja I and the results look good. He also reported some reliability issues between the T4i and the Atomos, so more testing is needed to confirm that it's a production-ready feature...

Woo-hoo!
and if there is no blackout like on 7D and 5DIII - come to papa!

got mine yesterday, no blackout when hit record, and from what i can see very clean low light,
autofocus is very loud and not reliable, even with the new 18-50mm, but i love the touch screen, it's very responsive and makes settings changes very fast and easy, this one is a keeper;

@ Buba - To confirm, when you connect HDMI (say to a TV or monitor) and hit record, the image is full-screen with no black bars around it and there aren't any graphics on top?

Information is also available here: Canon 650D (beta) test footage- "Morning with 85mm" by Johnnie Behiri on Vimeo

Can anyone confirm that the HDMI out is clean on the T4i?