Qui-John from the JC boards posts the following AOTC IMAX trailer description:

Regular-screen sized "green preview screen" (This looks so tiny on the IMAX screen, btw!)

Regular-screen sized Fox logo

Regular-screen sized "A long time ago, in a galaxy far, far away..."

Immediately into the full screen Star Wars logo and Opening Fanfare

The Logo then expands directly toward the viewer and off the screen, cutting to Yoda catching force-lightning.

"Size Matters Not"

Shot of Geonosis battle with Trade Federation ship crashing into ground after being shot down

Shot of Clone Transport ships in battle

"Except for IMAX"

Great shot of "Bruce Lee" Yoda

Flashes of arena battle

Brief shot of Dooku/Obi-Wan sabre battle

Shot of the Reek charging (presumably the shot where it's coming for Jango

Another shot of the arena battle

"Attack of the Clones: The IMAX Experience"

For more details, hit this JC forum link.