When they manage to serve ads as plain (non-flashy) images or text, and not rely on client-side scripts from third party sites then I might consider removing my ad blocker. None of these sites would be prepared to indemnify me against loss or damage due to malware from an ad served by their site, so I take my own precautions.
Why can't they use server-side code to serve up the ads? Or do they want to rotate them while an otherwise-static page is displayed?