GoodReads, LibraryThing, or Shelfari?

I currently have accounts at GoodReads, LibraryThing, and Shelfari. I can't seem to commit to a single one.



Of the three, Shelfari seems the least complex, which in some ways is an advantage. Also, I like their "bookshelf" widgets, such as the one I use over on the left column of this blog. But I find the interface is somewhat awkward, and I find I use it mainly for the widget and as backup.

GoodReads seems to be the most social. There are all kinds of ways to follow people's reviews...