It's been ages since I've seen a popup ad, but now that the IMDB seems to have implemented popup ads that circumvent Firefox's popup blocker, I'm starting to see them again. And it's not making me happy about visiting IMDB, let me tell you.
Come on, IMDB. Popup ads stopped being an effective form of advertising years ago. All they do now is piss people off. Are your other ads really generating so little revenue that you have to resort to popups? If you get so many complaints that you find it necessary to put up a web page justifying your annoying ads, that's a good sign that you need to rethink your advertising strategy.