I read something on the IGN page (I know, that there is not a lot of support for IGN, at least not on American and European pages) that basically puts another perspective on the "new" Xbox rumors.
Microsoft reportedly spent $ 500 000 on development of Kinect (may be a lot more). This means that if they release a new console, they will be kicking their own investment in the face. Unless they make the Kinect compatible with a new console, which would also be a bad move, as one would expect them to fully integrate the console with older compatible technologies, ie built in Kinect. They will milk every last cent out of the current platform and Kinect, as Virus786 mentioned.
I can't see 3D taking off with the current generation console, but it might be nice if it is included in the eventual future development of the next generation console. Adding on functionality to the current generation platform is nice, but I don't see this taking off. Then again, if everything I said was true, I probably would've been rich.