Bioware announced the details of their Guild Testing program for their upcoming MMORPG, Star Wars: The Old Republic. The programs allows entire guilds to be considered for the Game Testing Program, which is already underway with a few select guilds, however more guilds will be invited in the coming weeks.
If you want to join, make sure your guild has at least 10 registered members to be considered for Guild Testing. Guilds are then selected at random to participate. Currently European guilds are not eligible as the EU Guild Testing program has not yet begun, but will soon.
For more information about the SWTOR Guild Testing Program, then head over to the official forum post.