BenFriman - 8:12 pm on May 25, 2010 (gmt 0)
I agree with most on here who say that ads (preferably without animation or rollover effects) are fine when fitted neatly alongside the page content.
I disagree with Wheel who says:
"Instead, create something along the lines of a verbose directory, or pages with full descriptions. "
which, I think is getting into dangerous territory of implied endorsement. Ads should be very obviously ads and not confused with independent recommendation or editorial content.