The ability to force links to open in a new browser window has been around almost as long as browsers. Design advice that you shouldn’t use this technique has been around from day one, notably from renowned web usability expert Jakob Nielsen. It makes sense, as nobody wants lots of windows open on their desktop (or smartphone). But the domination of browsers which use a tabbed interface has changed things, right? Now that “open in a new window” links actually just open in a new tab, there’s not so much of a problem. Or is there?
Most of the people who study these things reckon nothing has changed. Opening in new tabs is considered almost as bad for the user as opening in new windows, despite the neatness. The main objection is that the back button opportunity is removed, and it’s just not ‘default behaviour’. I would agree, but I wouldn’t be too prescriptive. Apart from obvious exceptions (‘help’ text should always open in a new tab/window), there are occasions where you might need to take users down a product selection ‘tunnel’ which might take a lot of clicks to get back up. In that case, starting that journey in a new tab could be a great idea. The arguments have been going on for years – here’s a typical article with some heated discussion in the comments. Whatever you decide, just make sure that your website is consistent.