I use a hand-cranked version of this, and have been for over 10 years, I call it WebBookmarks.
It's a small bookmarklet that when clicked takes the current tabs URL and adds it as an escaped param onto the WebBookmarks URL and launches WebBookmarks. Then in the WebBookmarks form the Title and URL are already filled in, I assign a category, and click save. Job done.
I do this and do not use local machine bookmarks at all, as I use so many different machines (linux, windows, tablet, phone etc) during the course of a week, that keeping all those locally stored bookmarks in sync would be a nightmare.
It works for me, although I've not touched the code in forever so it's looking a bit dated - simply because it's rock solid.