TheForce.Net reports on the teaser trailer than has been recently released for Episode III.

You can view the trailer at one of the following sites:

AOL.com
Real.com
Hyperspace (Have to be a paid member here, apparently)

TheForce.Net also has a frame by frame breakdown of the trailer. (Look for the post entitled “EP3: ROTS Trailer Description - Frame by Frame” on Thu, Nov 04, 04 06:22:04 PM EST on their site)

[UPDATE: This site also has the trailer - http://www.dtheatre.com/read.php?sid=2791]