"@cdixon open sourcing it would be an enormous pain in the ass. selling it not as bad but yahoo infrastructure and auth problematic."
Besides that, open sourcing delicious wouldn't solve the problem - someone still has to host it, and maintain it, and import several million people's bookmark collections in to it. That takes significant time and money. Having the code is just a small part of it.
A smarter thing to do would be to campaign for the (public) data to be released as a huge data dump, ready for people to run their own analysis on (an Amazon Public Data Set for example). This too has plenty of problems though - under what terms should that data be licensed? People's bookmarks belong to them - would they be happy with their contributions being released as part of a massive data set for anyone (including sploggers) to do anything they liked with it?