I stopped using Delicious when i found Firebox bookmark synchronisation extensions (Google Browser Sync was it?) and now Chrome does that (and more) out-of-the-box. Google is on a good position to tackle that "market", perhaps better than Yahoo. Besides (about on the link sharing part), i [personally] already find lots of interesting links on HN, Twitter and the likes, which i store on the browser bookmarks and Google stores in the clawd
Is it just me, or would Xmarks and Delicious make a good match? Both live in the same realm, and both have large and interesting data sets. I know Xmarks has been purchased, but would a match like this make sense?