I don't get pop unders when I visit Google. I was just saying that because I wanted to post a safer site and Google appears to be pretty safe. I don't read the rules when I visit forums because I'm a member at over 100 currently and come back to different ones over time. Many forums/sites ban links to most sites, but Google is such a well known name that it's safer to post 99.9% of the time.
The reason I get things like this is I visit SEO sites and other peoples blogs. I'm always studying things and learning more, so I can figure out things. New ideas for just about everything. Google is my idea machine.
I want to visit the sites for the information, but I don't know which site has them and which site doesn't. They are pop unders and I can't always control that since some people stay cleaner and try not to annoy the visitors while others are trying to make a few extra bucks and don't exactly care about the visitor. It's personal choice over the matter with the webmaster of the site.