Tonearm - 8:15 pm on Jun 25, 2008 (gmt 0)

I have a Google PPC campaign and a Yahoo PPC campaign running. The Google ROI is much higher than Yahoo, and I think it's because of all the non-yahoo.com sites I'm showing for that are really low quality. I don't have their content network turned on. I emailed them about this and they responded that I can disable certain domains, but I don't want to constantly monitor the domains I'm showing for and add to a never-ending list. Has anyone found a way to increase the quality of Yahoo's PPC?