Mr Crunch had at look at Plum a few days ago, a soon-to-launch bookmarking service with approximately a gazillion features. From the site:
Plum lets you put all the stuff you care about, stumble across or need in one place. Collect and save from the web, your email, or your computer. Then personalize and share it with others (if you like). You can even discover other collections like yours and collect them too. In short, Plum is for remembering, reviewing, and remixing everything. Share your views, favorite topics, ideas, resources and knowledge with others. Tap into other people's collections and knowledge... all in one place - all at Plum.
I streamed Plum's DEMO presentation a few months back, and it seems like a well-intentioned app with a great team behind it. But once again it seems to fall into the everythingitis trap - what's the unique pain point that Plum solves? Like Wikio, eSnips and Yuku, it has some useful features but no specialization.