I've posted up at Smelly Cat a few times now for weekend work sessions and I've really enjoyed it. Their coffee is better than most that I've had in the city and their pastries are quite good as well. I've only ever been on the weekends but they get quite a bit of foot traffic here.
The baristas are very nice. It's a relatively standard set up with about 8 tables (three fun little alcoves) and one bar where sometimes people can sit and sometimes they have baristas using the Chemex. It can get crowded when everyone is standing around waiting for their drinks to be ready, but they work quickly. There is also some outdoor seating which is lovely, either on the sidewalk or the side of the building facing the parking lot. They always have music playing and I personally think they have good taste. My only complaint is the tables are a bit small (though admittedly, my laptop is enormous) and the AC is always WAY too high.
I will keep going back because I dig the ambience and the coffee ain't too shabby.