Halo 3 beta will be opened for registration at
halo3.com (beta has ended), and players and gamers from US, Europe and elsewhere on the world can log into the website join the unprecedented Halo 3 multiplayer public beta program. The Halo 3 beta invitations are likely to limited to a few select members, however, if anybody doesn’t manage to join or get in to the Halo3 beta via online registration, there will be numerous other opportunities to participate in the beta.
Halo 3 Announcement Trailer released during E3 2006 with HD trailer available on XBox Live Marketplace (video no longer available)
Another 60-second Halo 3 live action gameplay and CGI footage with CG animation TV commercial ad trailer will be aired during ESPN’s Monday Night Football on December 4, between 5:50 and 6:20 PST. The trailer was created by Hollywood FX house Digital Domain using assets provided by Bungie.
Update: More ways to join Halo 3 Beta.