Goodreads, Shelfari or LibraryThing?

Earlier this month, I decided to try out Shelfari and LibraryThing. I've been using Goodreads for a while now, and been perfectly happy with it, but after getting a Kobo Touch for Christmas, I thought maybe I could link it to Goodreads. When I found out that wasn't possible, I thought I'd check out other services.

So far, I haven't found much reason to switch.

LibraryThing looks like it would be good, but it has a limit of 200 books, and even if you pay for lifetime membership, there's still a limit.

I like the graphics on Shelfari, but it won't allow me to connect with authors like Goodreads does.

So I'm sure there must be something I'm missing with these services. Do you use Shelfari or LibraryThing? What do you like about them?

I don't think it will be long before I have an iPad or an iPhone. Goodreads has an app for that. Maybe I just have to be patient.