Social Bookmarking, Tagging, Blogging & Notes. Mmmmm, Notes.
Delirious follows on the conept of tagging content and sharing information and links by allowing users to subcribe to the RSS of each tag. Say you're interested in Search, just Wiki's, then find the right tag on the right, or simply alter the url yourself to find the Wiki tag and subscribe to the RSS to see entries from everyone else using the service interested in Wiki's - no, i couldnt find one on Search! not yet anyway, it is NEW ya know..
The difference, as explained here between delirious and delicious is that a) you can add notes, and b) you can use it as a blog.
How's this different from other social bookmark sites? Well, for one we're including the highly useful notes feature. When you post, there is a nice long "body" section to the form. I'm writing in it right now to write this! Also, the entire site is open source. See the buttons at the bottom of the page. You can hack the code in it's entirety. New and cool features are literally at -your- fingertips. Well, and your keyboard.
Im a big fan of del.icio.us, and i hope this new one runs just as smoothly, the ability to add notes is great, but although both are non-profit, will we see delicious add a notes feature to "keep up"?