I have been a long time user of Delicious with more than 2000 bookmarks. It might be the only Yahoo service I use with the exception of Flickr. Its idea was simple yet powerful - Make your bookmarks public and find like-minded people.
This was a key service for people researching on a particular field or simply hobbyists who spend an unhealthy amount of time obsessing over board games or gardening. Perhaps, Yahoo has been unable to monetise it well. But it has not even tried, as evident from the neglect it has been getting ever since it was acquisition.
As it might happen, Yahoo might open source the Delicious source code. I have heard that it’s written in Erlang. Perhaps this is the reason it has been difficult to modify or maintain. Nevertheless they could have open sourced the code earlier as Reddit has done and might have still monetized it.
Personally, this raises grave concerns for cloud apps that I use. Recently Stallman warned that “Google’s ChromeOS means losing control of data”. What happens if one morning you hear than gmail, facebook, orkut or flickr will be shutdown? What happens to all your data? What about the implicit interconnections you had formed and the communities that you had been participating in?
The clouds are getting ominously dark!
UPDATE: Yahoo! has clarified that they are planning to sell Delicious and not shut it down. However, the concerns raised about cloud apps still holds good.