I don't want to create a LibraryThing account. I'm pretty sure I already have at least two (if not three), PLUS Shelfari, PLUS one through NoveList... which I used for maybe three days on average before forgetting that I had an account(s).
Guess what works for me as far as keeping track of the books I've read? A pad of paper in my desk at work. I always know where it is. And it doesn't involve email, passwords, or remembering to check it and sign in. And my success rate is much higher than the electronic versions.
I know. I know. I really am a hopeless Luddite in some respects.
The funny thing is that I LOVE the idea of these online book things. The reason I have so many accounts is because I think it's fantastic and get very excited about it...and then I forget and don't use it and go back to my trusty pen and paper method.