I like Gymboree, and my son did too. It's a terrific place for a new mom to meet other moms and for little kids to make their first friends. The teachers are well-chosen and enthusiastic about their classes. The classes are programmed along the lines of the national franchise, so everything has a "scripted" feeling to it, but the teachers bring fresh life and vigor to the classes.
The cost seems high for what they offer, but the quality seems worth it.