I have a query in my mail box which baffled me and so thought would also share here and get a thought on this. If you say optimize your site for a low competition keyword to rank well in Google does that not mean you are also going for a less paying keywords in Google adsense and so though you increase the traffic you would not increase revenue ? I totally agree on this but then there can be a way like where you select low competitive keywords in Google SERP but high paying Adwords one.