Sterling, BB is my home and I don't really want to relive my time in EQ.
Zyke, I'm not totally integrated into the community but basically there are two top guilds: Ring of Valor and Reckless Ascension. I don't know RA's history much if they're a server transfer, split or what.
RoV has casual and raiding members, their casual membership raids twice a week in fairly easy raids. Their raiding members do whatever.
Cirlcle of Legends is still around, and they're working through TBM.
There's a bunch of other mid-tier guilds. You don't need to raid to get decent gear, and can do most of the content without raiding. So there's not much pressure to be in a raiding guild.