I was both a fan of del.icio.us (yahoo times) and later pinboard.in, but I'm more and more loosing faith and trust in the guy who operates it. No mobile apps (all third party, relatively unreliable, to one that I've used disappeared from the store overnight). Sometimes slow or down and no status page. Twitter account is being used for political messages on US politics (no objection against the expression of opinion - but why can't he use a personal twitter account instead of mixing it up with his business?). The Chrome addon broke and didn't get fixed (using an unofficial clone now). At least it's possible to export the bookmarks as html,xml,json - which I do regularly.

(Having said that: I have been a paying customer for years).