You need to ask yourself why you are keeping all this stuff.
The omnibox in Google Chrome is scarily good at re-finding stuff you have seen recently.
ListMixer is great for temporary ad hoc lists, and stuff that you might, or might not, look at again.
When I do add link to my personal bookmarks, I take a tip from Jay Baldwin's
toolbox Our tools are sorted by function rather than by name. Whackers, twisters, nabbers, and hole-makers live with their functional kindred. Just seeing them there together can give you an insight into how to do something more easily.
I say to myself "I shall need this again when I want to VERB [adjective] [NOUN] [adverb]
So, for example, the Listmixer bookmarklet is filed under "Keep," together with ones to subscribe to an RSS feed and make a note in Reader. Each main verb is a separate folder on my bookmark bar. By concentrating on what i might actually DO with the link, I avoid large collections tagged "interesting."