I know the system claims that it controls quality... but realistically, everybody knows non relevancy can be bought for the right price. I have to wonder how much this degrades the whole system to the point where many people simply don't trust the ads, no matter how obvious they may appear. When I can have an extremely relevant ad for a very niche one of a kind product get 50 impressions and not a single click... even though there is virtually no legitimate competition in the other ads... I have to think it's degraded quite a bit.
We are being outbid on niche terms to the point where some ads won't even show up any more.
Yet the ads that DO show up are mostly totally irrelevant, go to link farms, Adfarm-only sites, or shopping comparison sites.
To find an actual ad for an actual product is getting harder and harder.
If things don't get better soon we will probably drop all but about 5% of our ads/keywords, which is the very small number of really well performing ones.
Lucky for us we show up pretty well in the raw searches for most SE's. But it sure will be hard for a new business unless they have a ton of money to spend to beat out eBay, Amazon, buyfornothingdotcom, and the like.