So many people believes pop-up ads create more revenue share comparing to other type of ad units.But it's one of the biggest online advertising myth and the truth is entirely different.
Less ads is always good for a website or a blog.But if you are someone who wants to earn money from the blog then you need to focus on ads too.But take my advice,don't put pop-up ads or curser ads(which moves around with mouse arrow) in your page/blog/website.Put all the ads you need in your sidebars and footer.Or if it is a CPC ad,you can blend it in-between posts so that it won't disturb the readers eye.You really don't have to put CPM ads inside the posts/articles because anyway sidebars and footer of your page will load with the post.
And there is no guarantee that your pop-up ad will be seen by a visitor because pop-up blockers are one of the most downloaded addons used in web browsers nowadays.So why to waste your time brain on pop-up ads??!!..
Remember an angry and annoyed reader is more dangerous for your page than someone who never visited your page.