Adventure Developers has a nice (long) article up about the state of adventure games. Beiddie Rafol does a nice job of attacking all the angles, including marketing, distribution, etc.
From first-hand experience, I can tell you that if you even utter the words "adventure game" in a meeting with a publisher you can just pack up your spiffy concept art and leave. You'd get a better reaction by announcing that you have the plague.
Publishers are silly.