You need to automate everything if you want to be successful in measuring customer satisfaction. Surveying your customers is a great way of measuring customer satisfaction but if they take too much time away from other important work, it will fall by the wayside. Automate both your requests for completing the survey and your collection and reporting of the data. Some help desk management software will do this for you. If yours does not, consider customization that will enable it -- it's worth the investment.
One of the best ways to find out how effective your customers think your help desk or forum is, is to take a survey.... ask the people who actually use the help desk or forum what they think about it. Asking for suggestions to improve your help desk or forum is a good idea. There are many approaches to surveying, but some are more effective than others.
Often times membership websites will send a customer satisfaction survey of their help desk or forum to their entire list. There are several problems with this approach. First not everyone surveyed will have used your help desk's services. This will either make your percentage of responses low or add irrelevant responses to your data. Since you only request this information once in a while, you will be tempted to cram too much information into the survey. Often these surveys lack focus and do not give you a clear picture of performance.
A better approach to help desk or forum customer satisfaction measurement is case-by-case surveying. Each time a case is closed, meaning the problem was resolved and the resolution was already communicated to the requester, a short survey on the case is sent to the requester.
This is great information for continuous improvement and you can review the comments provided by your customers.