Barry Rowlingson gave an interesting talk at UseR 2011, “Why R-help must die!” He suggested the Q-and-A type sites Stack Overflow (on programming) and Cross Validated (on statistics), both part of Stack Exchange.
An interesting feature of these sites is that, in addition to voting up and down on the questions and answers, one accrues reputation points. I’ve found this to be surprisingly addictive, and perhaps that’s the goal. Consider the O’Reilly book Gamification by design.
I agree with Barry that these sites are an excellent replacement for R-help, which I stopped paying attention to years ago. The format is easier to read, math and code can be nicely formatted, the questions are tagged, search is easier, and there should be less redundancy.