There are two kinds of exit pops.

One is javascript exit pop that triggers when a user closes window or leaves a page. This method traps the user's window with javascript alert preventing them to go back or do whatever they were intending to do. Google kinda frowns upon this method because it can be considered as manipulation of your bounce rate with trapping back button behavior. So you stand risky chances during google manual review or if a bot checks of your code (if google scans your code to find things like that). Also you can only use plain text in the alert window. There is no way to style it or include images.

Second method is firing a pop up with lightbox window when a user hovers hidden 1px line at the top of the browser window right under the toolbar. This captures user's intent to click back button or close the window as they move their mouse over the toolbar. This way you get the same result except you don't take your user's browser hostage and if they don't like what you have to offer they can still go back, close window etc. This method is more user friendly, SEO safe and can deliver same results or even better because you can include images, videos or any html content in lightbox window.

I am currently developing a WordPress plugin using second method. The plugin would pop a lightbox window with Amazon products relevant to the page content. If you interested you can check it out and reserve your free copy. The link is in the signature.

It wouldn't have effect it sometimes ago if you weren't using adsense,cuz there wouldn't have any manual review.But google is now hiring many people only to manually review sites and give them quality score.I wouldn't go close to anything like exit pop up if i were you.Exit pop up never was for the seo guys.These are for the marketers who does viral traffic like social media.Stay far away from it if you r trying to rank your site.

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