You can read the details here, but remember that your chance to attend the event will begin tomorrow (Thursday 11/10.)
I was able to pry a few more details out of the events team:
* Xbox 360: Zero Hour is located about an hour to an hour and a half outside of LA and will provide you with the exclusive opportunity to get exclusive access to hundreds of gaming areas with dozens of new games, many of which have not yet been made publicly playable.
* There will be enough consoles available on site for every attendee to purchase their own Xbox 360 and be among the first in the world.
* Zero Hour will also provide you with exclusive event giveaways such as collector’s edition faceplates and offer around-the-clock entertainment such as a live performance from from emerging artists Louis XIV, various DJs and others, as well as game demonstrations, Xbox Live matches and much more .
The event is an exclusive event for those who are the first to register. The page I linked to above will have a registration link starting tomorrow, but I don’t have an exact time the link will appear, or further event details.