Del.icio.us, Technorati and LibraryThing

I'm stll trying to catch up with my KCLS Learning 2.0.
Deeper we go into Internet it becomes darker!!!! Internet is endless and bootmeless!!!! AU-U-U-U!!!!
For my Del.icio.us look like one more blog search engine!!!!
It' interesting to learn more and new BUT will I remember all this later - this is the most important question for me!!!
I liked browsing in Technorati, found some interestig blogs - probably will use this searching blog engine in future too!!!!
And I learned new word Folksonomy - everybody can use their own keywords to categorize books.
Today I created MyLibrary on LibraryThing - that was fun, I played with couple of my own books in couple mins and I'll add more books later. I liked Tour and specially one phrase: "LibraryThing cares about books, not about SELLING books". I'm a librarian and it' impotrant to me too.
I checked GuruLib and Shelfari.