I'm 45, and I agree with both of you. There seems to be a bimodal thing with lots of folks who are still young enough to think that screaming THE TRUTH(tm) to everyone they encounter will be what fixes the world, but a very large chunk of active posters who actually want to communicate seem to be a bit older. My personal theory is that the API exodus left year gathered in a lot of people who had seen previous social media sites (e.g. Digg) blow themselves up, and that by definition will skew older.