As the comments in the article suggest, this is a completely unreliable datapoint. I've just got an iPad and the iBooks store sucks - there's barely any choice.

As the comments in the article suggest, this is a completely unreliable datapoint. I've just got an iPad and the iBooks store sucks - there's barely any choice. But I can download the Kindle app and can buy Kindle books, so I'm fine. I dare say that a lot of iPad users prefer shopping at the Kindle store over the iBooks store. Jobs is probably talking about 20% of the Times best seller list but on the long tail, Amazon has it beat for selection