The contextual ads are on topic enough, but not exactly interesting:
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Persecutor, Joraga, OmnathPersecutor, Joraga, Omnath
The problem with contextual ads (this goes beyond just Google) is that they look like someone cut out a bunch of classifieds and taped them on your monitor. People going to your site are looking for answers to questions, some of them might be enticed to cash in on a good deal if they actually noticed it.
I would recommend Amazon / E-bay image links with the least amount of clutter as well as a mix of other affiliates. You might consider running your own ad server, such as OpenX to track and tweak your campaigns.
Additionally, in my experience, ads that interrupt the content that the user came to see get far less attention than the non-irritating 200x200 square to the right. Did you try using image only ads in that location?