Ezo, getting lots of lurkers is normal. Most people on forums want to read without making a comment, either because they think they don't have anything to add to the discussion, or because they are worried about the reaction they will get, or because it's quicker just to read. Dellux, you could try alternating Adsense on your forum with another affiliate programme, to get a good comparison. Either put Adsense up one week and another one the next, or do it alternate days. Then you'll be able to see which programme performs the best for your site. With Adsense, it's not the best solution for all types of website so you need to experiment.