It's not yet clear to me that these pop-ups are mostly un-useful for me, since in some of the few instances I have seen them they have conveyed information such as "you really don't want to waste your time clicking on this link" or "this link is more interesting than it looks." The question for me is what downsides I experience and whether they outweigh any possible benefits. Some potential downsides to be on the lookout for being already outlined by Sabrina.