Dana Blankenhorn has an interesting post titled Marketing is the billion dollar question in open source. I definitely agree with this. Good marketing of a project can make it successful, and bad marketing can kill it. It really is the hardest part of being an open source developer. Sure it's fun to work on this stuff until the wee hours of the morning, but if no one (including yourself) appreciates your project (due to your lack of marketing), it really worth it? Compare that to wild enthusiasm by your users and people writing articles about your project. There's a stark contrast there.