RangerX - what was there to indicate that completing this survey would earn an Amazon.com gift certificate? Was there any banner or other indication during the survey when you did it? Did the information you receive state "when" you'd receive the gift certificate?
It's great you're posting these "free" things, but you should include some background information on a deal when you post it, especially if there's no information on the website you link to to get the "free item" such as in this case. It's going to save you from having to answer a bunch of qestions, after the fact.
Again, thanks!