My problem with delicio.us was always the amount of time I had to devote to managing everything. I had to manage the links, the tags, my page, the plugins, etc... It's a wonderful service, but I always froze in that moment of bookmarking: what do I tag this? Where am I going to put this that I remember?

To that end, I've been trying historio.us. I'm not so sure about it, but I like that I just click one button and I know that if I really have to find it some day, I can. They killer feature that would make it truly useful is some sort of auto-filtering for what you're inputting.