Should links open in new windows or not? Some insist that a target=”_blank” in external links makes users stay on a site longer. My answer: Don’t. Do. It.
It’s well-documented why you should not. In short, users are smart enough to open a new window when they wish, and would like the use of their back button, please.
The above rule applies when the link is directly related to your content. For instance, your page is about pet food and you link out to Eukanuba. Perhaps the user is done reading your site, in which case she will just click the link. Or perhaps she wants to keep your article open a while longer, in which case she will open the link in a new window herself. Her browser, her choice.
Caveat: it is acceptable to open a popup window if the link is unrelated to your content but requires user action, for instance, paying a visit to Quicktime.com in order to view your video.
Why? Because in the Eukanuba case, the user is on a pet food thought train. She doesn’t want her thought process interrupted. In the latter case, you are actually forcing this interruption, with good reason. You are saying, “Sorry, as a quick aside, you have to do something completely unrelated.”
So there you have it. Are you linking to related content? No popup. Unrelated content? Pop away.