Why Firetower? First and foremost, it's on my walk/hobble home. It's also got wireless, and it's got a pretty decent atmosphere. I know several people prefer the General Merc. Two very different experiences - the Merc has lots of nooks and crannies that you can hide in, while Firetower has a much warmer, more open feel.
Anyway, I kind of like this ritual of stopping in here Friday afternoons - I tend to waste time: I went a bit nuts with posting last Friday, and I spend lots of time on MySpace . . . it's kind of fun to just zone out and waste time while people watching.