Unfortunately someone would raise a privacy stink just like they did for the netflix prize data and the aol search data. This is why we can't have nice things.
But Delicious's database is already public (if you take out private fields on the user table and the private links). Even just the links + tags without any user info would rock for semantic Web usage.
I heard that there is this thing called "the cloud" where you can rent services based on the work time. That makes cheapo servers both realistic and quite simple ;)
Actually I just noticed you get 750h of free micro instance time from aws... I wonder if it would be worth doing. I imagine the link+tags are <100GB in total.
