I don't want to be the one to rain on your parade, but no one here is using the correct settings. I'm sure everyone here has heard of the general rule of thumb for daytime exposures- "Sunny 16." There is also a rule of thumb that applies to moon shots- it's called "Moon 11." Everyone wants to over expose the moon. In doing so, you are losing all the detail. "Moon 11" = 1/ISO @ f/11. Of course this has to be adjusted for different phases of the Moon and this formula is for a full moon. You can't shoot an object that is brightly lit by the Sun wide open and expect good results. Also, slow shutter speeds will yield poor results- as some on here have found out.
Here's an article on "Moon 11"-
http://www.astropix.com/HTML/I_ASTROP/TRIPOD/TRIPOD4.HTMTo figure out the proper exposure during different moon phases, use a "Moon Exposure Calculator":
http://www.adidap.com/2006/12/06/moon-exposure-calculator/I'm quite surprised no one here knew about any of this, it's pretty standard stuff.
Here's one I took with a 400mm f/5.6L + 1.4x TC II:

Also, you will always have better results shooting a moon that is less than full. At full moon, the sun that's illuminating it is just too bright and you loose a lot of detail. One of the other posters in this thread is correct, the longer the lens the better.