Just went to the Elder Scrolls wiki to look for any info on Skyrim, and it says in the latest news it has been confirmed that Skyrim is on a new engine: http://www.uesp.net/, and heres the actual tweet regarding the new engine: http://twitter.com/nickbreckon/status/14015054991069184#
This is the best news i've heard since on Skyrim so far, i was getting sick of the Gamebryo engine.