gobalicious said:

I can't help but notice Yoda's ears. They vibrate a lot as he moves his head. It seems that real cartilage is stiffer than whatever the puppet is made of. Try flicking your own ears.

Although that may be true, two things:

Your ears are not as long as Yoda's. I think the amount of ear we're dealing with here matters.
I distinctly remember some AOTC behind-the-scenes type thing, talking about making the CG Yoda for the first time, saying that they had tried to recreate even the little stuff like his ear wiggles, in order to get the CG-Puppet just right. It was driving Frank Oz crazy, because they were recreating things that he considered mistakes (the ear wiggles were the example of this), but Yoda just didn't look like Yoda without those. Point is, Yoda's incredibly wiggly ears are, in essence, canon.