If there's one thing I really enjoyed about WoW, it's the raiding guild I use to run with. We were kinda sorta on the casual side of progression, but we still had a good balance of fun and competitiveness. I made a lot of good memories with those guys back in the day, and I'm still friends with some of my guildees on FB. In fact, they have a reboot going on right now that I'll be joining in on during the Winter. Since most of us have more real-life stuff going on than we did back in the day, I'm pretty sure we're going full casual for the reboot.