Barb, I like this short list.
Having tried all of these techniques, I would like to share my own personal experiences:
Surveys -- surveys are powerful just as you say, although they tend to be short-lived in effect.
Wikis -- these have a fairly limited range of use. Usually they are good for community compilations of facts or data, such as Wikipedia or SmallBusiness.com or Taxalmanac.org. Some companies get the biggest use of wikis internally, and not as customer-facing vehicles.
Podcssts -- these recordings secure deep engagement from those who like to listen and are fabulous in that regard. However, I have found that only about 10% of your customers will download / listen to podcasts. But for those who do, your message tends to get 100% mindshare (on a plane, etc.). You can double the usefulness of a podcast by having the recording transcribed and making it available as text.
Blogs -- writing a blog is likely to get the best, broadest, most long-lasting response out of all of them. The challenge comes if you do not like to write, since you will have to tend a blog regularly and fill it with content. Some companies manage this drawback by turning it into a team blog, with multiple writers from one company sharing the load.
Finally, don't forget the venerable product forum / discussion board. Especially for new technology products these can be extremely helpful not only in responding to customer support issues, but in building a community of loyal customer evangelists.
Hope my experiences help.
Anita
