i feel like i used to see them like crazy about 4 years ago, but most of those people ride geared bikes now. i see a few kids (saw a fuqing suh-weeet 3rensho the other day!), but more that look like they are fixed until they start coasting. we have way more single-speeders now than any other period in recent memory.
i have two friends who ride fixed, and we pretty much ride only for transport, if there is somewhere to go, bikes are always the choice.
even with only three of us, it is mad fun to do the one beer per bar thing for the evening. it's better than sitting on your ass all night!