Let's recap first. Just Cause let's you play the role of an american special agent, with the mission to bring peace in a country composed of islands. Yes, all by himself. It doesn't seem that incredible, but keep in mind that the country is big, *really* big. Just Cause also uses a non-linear mission system like GTA3, which is good since there are many of them. And the very nice fact is that your character can do some pretty awesome and completely unrealistic things. He's not a super-hero, but some of the stuff he can do is borderline crazy. This is one of our biggest surprise for this E3.
As mentioned before, this is still a very much work-in-progress version requiring a lot of polishing. The pop-in/clipping/shadowing issues will of course be fixed in the final version.
Update: A big "thanks" to Mark of XFERLA.com, who provides us a pretty strong server to host the video. If you have issues to download the file from the USA, this mirror should come in handy !