Open question: How could Yahoo have monetized delicious?
I'll start: Use the browser plugin to deliver highly targeted but low profile ads to users. The targeting would be based on the longitudinal interest data they have for millions of users, many of whom have been tagging their interests for months or years. For active users, I think this data is better than facebook targeting info.
Another angle; recruitment, at least for software developers. For active users, del.icio.us is one of best reflections of your skillset out there, with the exception of github. Potential employers or headhunters pay to search for matching profiles.
Yahoo! keeps saying it's a content company. Given what they knew via delicious, it seems like a competent production group could have noted the top marks in any category, figured out why they were so successful, then combined them into a product with commercial value, either licensing he content directly, or commissioning the original authors to develop their ideas on Yahoo's dime, then subdividing this nicely vetted material by proven authors for use across a range or properties (e.g. photography related stuff in Flickr, investing references in Yahoo! finance, etc.)
I'll start: Use the browser plugin to deliver highly targeted but low profile ads to users. The targeting would be based on the longitudinal interest data they have for millions of users, many of whom have been tagging their interests for months or years. For active users, I think this data is better than facebook targeting info.