You can now see the Halo 2 announcement trailer on Xbox.com. They are now allowing you to download Windows Media player 9 from the site also, though I recommend only download the trailer from Xbox.com if you have a fast connection, otherwise you will have to wait an hour, and the trailer while it plays will lag very badly.
If so, try these other websites allowing a little more blurry(very small blur but you can still tell, how good the graphics are.) quicktime formats for the mirror lists click this link:
http://www.bungie.net/perlbin/blam.pl?file=/site/1
or for a direct link to one of them I recommend this the most click here:
http://www2.mythica.org/halo/hbo/hal..._qt6_small.mov
Enjoy!
-Al the Vykker