Yes, but you don't get things sorted in order in del.icio.us (I liked the old URL! TLD puns, FTW!), you just get them lumped by tag and, what, in reverse-chronological of when they got bookmarked? That's useful, certainly, but then you get things like "ficlength:1000-5000" in hodge-podge order, rather than ranged from the 1,100 word fic to the 4,980 word fic. (Unless there are features I'm not aware of!)

You are aware of all of the above, I know! I'm just think-typing out loud, here. (And quietly shaking my fist at LJ for not allowing me to sneak in some fancy "refer to this database" code, boo!)