Assume that lots of people have tagged bookmark collections in lots of places. What if those sites all supported PubSubHubBub and/or RSS Cloud across feeds by dimensions of tag, user, and URL?

I think you’d have the makings of a loosely coupled and distributed Delicious:

The motivation to maintain individual and group bookmark collections could match up better with those who care about them. You could use pinboard.in. You could host your own bookmarks. You could be a minor hero and host those of the people you find interesting.

Then, imagine a layer of search engines, each specializing in collecting a topically-interesting mix of real-time feeds from an array of social bookmarking sites. A future Google could subscribe to hubs pings from all the above and build something interesting and valuable without hosting the bookmarks of pesky, demanding users.

I don’t think this is super-science rocket surgery. Oddly enough, this is close to how I hoped we’d restructure Delicious back in the 2.0 days

This is pretty much what I was thinking when I was talking federation. I actually think the comments about hosting your own are too simplistic.

I find it a pain to handle hosting, it's so much harder for less technical people.

"Anyone" can host a WordPress blog (as an example), but I've also seen "anyone" get screwed again and again by not knowing about backups, domain registration, getting hacked, or a ton of other things.

I'd like to sign on to a bookmarking service that actively pursues federation.