I was observing Google results for months to determine if pop-up ads have a negative impact on SEO. Regarding my observations, sites without pop-ups usually get ranked better. Actually, that doesn't really prove anything since most of sites without pop-ups have better content too!
Anyways, does anyone know the effect of using pop-ups in regards to SEO? Can Google or other search engines find out if your site uses pop-up ads? Do they run java scripts for this purpose?