I've been speaking with many SEO professionals and one recently mentioned that Pop-Ups or Pop-Unders may be hurting my ranking. Has anyone seen this result?
I would avoid pop-ups like the plague. I'm not sure about it effecting ranking but it really blackens the user experience. If users don't think that pop-ups give them viruses (and many do!), then they will certainly not appreciate what is seen as spam exploding in their face and will navigate away from your site asap.
Yep, even with pop under. Feedback from customers? No need of that. Back then many websites are using pops. Even the gurus and "gurus". Now, we barely see one. If it's so effective why would they throw it away? It's just a common sense.