This would be great. The theme doesn’t have to be much, just have two views, one image grid for visual bookmarks and one list view for useful, easy to access links. Following your approach outlined in the article (categorisation etc.) I think it could really take off.
Like you said, future options are endless. Sticky posts for our most frequently used links at the top etc. Ajax enabled search/filtering for quick results etc.
I don’t know about anybody else but this help my workflow for sure.