I tried it, but actually using it to create lists of books is effectively impossible. It lets you click one of the 5 books it shows you, or you can manually search every book. It's a brutal experience. Goodreads letting you go through your books as a table and checkbox which books to add blows it out of the water.
I might self host it so I can see what options I have to either make a new page to make lists in a way that's actually functional, or see how the data is managed to write a script to import those correctly from goodreads, but it's extremely painful to do right now. (Edit: OK, looking at the code base it's a bit more involved than I can be bothered with at the moment. I'm spending the time I can do development on other stuff. I do like the idea of the service, but right now the limitations just make using it to organize my reading unrealistic.)
Admittedly it's young, and I appreciate that being open source means that it's something I can roll my own spins on, but right now it's pretty rough.