Recently I merged my four Delicious social bookmarking accounts into one Pinboard account. I now realize I should have done that years ago because Pinboard's functionality is more streamlined, it's faster and safer than Delicious ever was.
Yet for me the biggest advantage of that merger is that I found Pinboard IncSearch. Search queries instantly return results and scrolling more convenient compared to using the website. Offline too.
Furthermore in a way it's even smarter than Pinboard itself, because you can use operators OR("keyword-a|keyword-b") and NOT("!keyword").
I always had the desire to not only do social bookmarking but even use it as a scale out knowledge base. After ten years it accumulated to 4700 bookmarks (https://pinboard.in/u:eocas) with around 1000 characters description each. Managing it without Pinboard IncSearch was a pain and now its the first place to search a familiar topic. It's literally worth gold and I recommend the combination of Pinboard + Pinboard IncSearch to every researcher who requires practicality and speed.
What's on my wishlist are clickable tags.
When on my next FLATTR round of returning love to awesome open-source software, Pinboard IncSearch will certainly receive a token.