You can download your own copy here via a variety of links. The quickest links are probably the Bittorrent ones -- my copy downloaded in about two minutes (though at less than 9 MB it's a quick download any way you get it). If you haven't tried Bittorrent yet, give it a go. It's a P2P download method, but instead of your PC just downloading the file from others, you also upload the file as you download it. It's hard to explain, but it usually means quicker downloads for me than with traditional P2P apps (Kazaa, Gnutella, etc.)
About the trailer itself: It's 90 seconds long. The first half is the late Sir Alec Guinness narrating footage from Episodes I, II, and IV, then it delivers the good stuff: shots (and voice) of Darth Vader, Yoda, Mace Windu, a space battle, Padme and Anakin, and the climactic lightsaber duel between Anakin and Obi-Wan. It's better than the early teasers for Episode II (quick snapshots with Vader breathing audio), but it doesn't reveal much of anything about the story. Which is the general idea, I suppose: get the fans excited, give them a little eye candy, and remind everyone else that this franchise has one more installment on the way. I'm trying to stay positive about this movie, even though the last two were disappointing. Episode III could be the one that redeems the prequel trilogy, or it could put the last nail in the Star Wars coffin. Either way, I can't wait to see it.