If a guild is well-moderated, it's a nice little getaway from the sheer idiocy that has invaded much of the rest of Gaia.
However, if the crewmembers are bad at their job, and the userbase is retarded to begin with, it's really a lost cause.
It definitely looks like activity in guilds doesn't really count towards achievements, though... : ( Which is a mixed blessing.
The Any Topic Guild
I will find you... on Gaia! :D