certainthings

I could never get used to the new Delicious, maybe I just missed the old one too much. Back when the old one went belly up I checked out Diigo, but like most alternatives they have a problem with porny links. In the end I went with Pinboard. It does have downsides (one-man operation, he's v. slow in making improvements, the search is buggy and you can't search tags or exclude them from search). But Pinboard dude is v. fandom friendly, the site useable and makes bookmarking easy, which made it worth the $10 for sign-up imo.

I don't have experience with other bookmarking sites and can't help you there, sorry.