Okay, this image is looking good. There's definitely some J.J. Abrams-style lens flare going on. Not really sure why this Jedi is standing in the middle of a field with an ignited lightsaber, but still, I'm digging it.
In case you didn't realize, the guy in the background is Darth Krayt, one of the most prominent EU Sith Lords. The casting titles are complete baloney (everyone except Mark Hamill hasn't even been rumored for the movie), but the below-title text is pretty cool. It's signifying that Darth Krayt is one of the next great Sith Lords. And of course, the subtitle "Legacy of the Shadows" isn't too bad. Of course, it's one of those classic titles that has a mysterious sound to it, but makes absolutely no sense when you think about it.
You'll find that a lot of these posters have alluring and mysterious promo text at the top. I suppose that the art, as well as the "The evil never ends, just evolves" thing could imply that either Darth Vader is still alive (and "evolved" out of his suit), or a new Sith is going to take his place. Most of these posters are high-quality, but the art doesn't specifically make any sense at all.
This is one of the completely false posters that I was talking about. This poster is basically the result of a huge franchise-movie collision. And I would TOTALLY go see it.
Again, this poster implies that Darth Vader survived his death in Episode VI. I certainly like the art, and the promo text is cool, except for one devastatingly obvious detail: "survive" only has one "i". I get it, it looks cool, but seriously guys, learn English.
It looks like SOME red-lightsaber-wielding dude is stalking the Falcon.
Very nice artwork...but why exactly is there a Star Destroyer crashed in the middle of an ocean? Just saying.
I actually saw this image several days after I originally released this post, but it was so good that I had to update it. There's Star Destroyers, TIE Fighters, and some great icy mountains. Again, this suggests that Darth Vader is still alive, which is a very common theme.
There are a lot more posters, but most of them are pretty low-quality and the images don't make much sense. We can only hope that these posters will inspire the Episode VII crew to make something even better. May the force be with you all!