Matt, While I like how Pinboard looks and I hear it’s got a reasonable API, it’s still just another me-too-service like delicious and could potentially go down at any time. Admitted, as a paid service, it’s a bit less likely, but what happens if/when the owner dies or decides to sell it off? I’ve decided that owning all of my bookmarks on my own personal website is really the best (only?) way to go. Other options and thoughts can be found here: http://indieweb.org/bookmark.