The following images have been floating around the internet today. They appear to be screen shots from the 4 preview clips that were shown at Comic-Con; however some of these images are from clips that were not released to the general public via any official channel. The first 2 images are from the planet Umbara, the next 3 are from a space battle, and the final one is from the "Water War" preview clip released on StarWars.com. To view these images in higher resolution, either download them or view them in a different tab.
Check out my Season 4 preview article here for full coverage of the Comic-Con panel and the two clips that were released publically.
UPDATE: This image of Rik Enson was just released by MTV.