"It's not possible to do today's 3D because there are a lot more frames for left and right eyes that Component Video cannot handle"
This is not a valid reason. Rendering a game with a 30fps cap fits well within the 60hz progressive limit of component video, using full frame video. Side-by-side, or interlaced 3D frames also entirely bypass this framerate limitation, as you can get 60fps inside of 60hz by displaying two rendered frames inside of each component video frame. Hell, you could run 60fps 3D video inside of 480i composite using side-by-side, if you wanted.
LovingDVD - 3D support on the 360 is on a per-game basis. Different games support different formats. There was a game on Xbox Live Arcade that contained a large variety of 3D options, but the name of it escapes me at the moment. It was something of a side-scrolling kung fu game. If I understand correctly, on the PS3 3D support is more of a system-wide thing, where games rely on a system software setting to enable 3D instead of needing to bring their own solution to the table.