New type of HDMI cable?
Simple answer - no there is no need for a new HDMI cable for current 3D TV.
The current crop of 3D TVs produce the image for each eye by using alternate lines with a polarising lens on each line. They can either be fed with a signal that already has alternate lines-per-eye or with a signal where the left hand side of the screen is for the left eye and the right hand of the screen is for the right eye (the TV does the interleaving before display).
The problem is that pre-interleaved gives you roughly 540p per eye and l/r gives you SD per eye. I believe that they are working on a new version of HDMI to allow 1080p per eye, which given the extra bandwidth this will require, probably means a new HDMI cable.