The audience for delicious is quite different to the audience that provides the most eyeballs and clicks that power the actual revenue generation at Yahoo. So

The audience for delicious is quite different to the audience that provides the most eyeballs and clicks that power the actual revenue generation at Yahoo. So pissing off delicious users won't have any serious financial repercussions. And since it seems plainly evident that Yahoo are now hunkering down in pure survival mode with soccer-mom content plays, it's unlikely Yahoo will need the support of early adopters for the rest of it's shortened lifespan. Delicious users are mostly using the eco-system of tools rather than the website itself, so there's not much to be gained by splattering it with ads. The only time I see the delicious site these days is when there's a link in my inbox from a contact - and that's edge case for the vast majority of delicious users.