And in a forum that's devoted to technical support, for computer-related or other products, that's certainly true. In fact, managing technical-support forums raises a whole host of other issues. The best part of an online technical-support forum is that it lets users cut through the marketing noise and find out what works and what doesn't. If the Turbo feature doesn't work, letting customer post public messages about their problems with it will make the fact undeniably evident. It's a fact of life.
Customers are more satisfied, because they have no hold time or long-distance charges.
A junior tech, with backstage help, can do the work of a tech-support manager, and users who help each other don't require any staff intervention. But from the sysop point of view, you must give users a reason to prefer this low-cost channel to the phone. It's an interactive environment. Inevitably, experienced users will chime in with their own angle on a problem. Whether you want it or not, there will be discussions of competitive products, even comparisons.