I guess I always saw "lectures" listed next to movies, dance, theater, and so on, but somehow I never connected them to entertainment.
I must be an adult.
Seeing how Rachel prepares for her "performances", having prepared my own, having gone to a lecture about Darwin's influence on American culture last night, and recalling all the TED presentations I've now seen, I am now connected to the fact that lectures are entertainment. One man/woman plays.
Even more: lectures are verbal blogging. A post in a series of posts and responses in the continuous global forum.