Delicious is a cool resource. I am constantly bookmarking sites that I visit frequently and really like the idea of categorizing the bookmarks to simplify the search. One feature I like with bookmarks in general is when you start typing in the address, the bookmark appears and you can click it to take you to that page. It truly makes surfing the web easier and certainly saves time. Bookmarks add up, and can be a bit congested, so this feature certainly helps.
I can already see this being useful with my coaching. I bookmark alot of sites that are for new skills and training plans, and now to be able to categorize them really helps with my organization!