An intriguing little fire-fight has broken out in a normally quiet forum I frequent, to whit: new windows, Spawn o' Satan or God's Gift to users? I confess, shame on me, to have given the matter precious little thought. Till now.
Personally, I've always preferred links to open in the same window. But when my reader made representations to me that she preferred links to open in their own window I was happy enough to comply without, as I say, fretting over much. Nothing now forces me to take a stand, except that the altercation I alluded to pointed to a couple of interesting links on the subject.
Jakob Nielsen, who I regard rather highly, rates messing with the back button and opening new browser windows as the two deadliest sins of web design. And having read his piece, I'm inclined to agree. Nielsen's point is simple: by opening a link in a new window, you rob the user of control, and the web is all about giving users control. He says that "the Back button is the lifeline of the Web user and the second-most used navigation feature (after following hypertext links)". I'm inclined to agree, now.
The flipside is that if the user wants to open a link in a new window then, of course, she has the power to do so. OK, so the user has to know how to do that, but in general I reckon one is better off assuming that users are smart. If they aren't smart enough to open a link in a new window, then maybe they are also not smart enough to work out why the Back button no longer works when you opened a new window for them.
Question: if all browsers offered tabbed windows, would it be acceptable to open a new tab? Probably not.