We are currently looking at a bunch of different ad software for our new directory:

http://www.adcycle.com/

http://www.adserversolutions.com/

Where looking at a few others, anyone please help

Joe

Joe-
check out phpadsnew, as that is what this site, sitepointforums, and a few other heavy hitters use. They have a great admin control panel, and great statistical reporting. You can even give advertisers a username and password so they can upload/change their banners, and login to see how many impressions they received for the day/week/etc..

Yes I can vouch for phpadsnew too :)

www.sourceforge.net/projects/phpadsnew

It looks rather nice I might add