Which Alliance guild is the largest on the server, member wise? Anyone know offhand? Or is there not one behemoth on BB?
What can I say. I like my guilds like I like my women, big.
It depends on what you are looking for out of the guild. If you want a levelling guild, then CASUAL has been just scooping up all low level players, often with unsolicited invites.
For raiding, there are a few guilds with 3 raid teams, which are Valhalla and Serendipity.
There are plenty of “regular” sized guilds that are also quite active and will likely meet whatever needs you have.