However, I do wish you'd been specific about what statements about FaceTime you consider to be a lie. Now I'm forced to guess. The only issue about FaceTime that I can guess would be controversial was the claim that the protocol was going to be made open or a standard, or that something might be open sourced. (I'm thinking it was the former.)
I don't think this was a lie, but an error. I suspect that this was probably Steve Jobs idea and a decision he made at the relatively last minute which turned out to be problematic either because FaceTime uses technology that Apple had licensed, and thus couldn't open source or a protocol that was licensed and thus Apple couldn't standardize. Or, it may be that they are in the process of doing this, possibly with some standards body, and are mired in bureaucracy?
I really don't know what happened (I don't even know the specifics of the alleged lie).... but in order for there to be a lie, I think there needs to be more than just saying something that is not correct.
There are lots of sources of error- misremembering, misunderstanding, misbelieving, or misspeaking. There needs to be an intent to deceive for it to be a lie, in my book.
This is a positive defense of Bill Gates too-- was he simply in error? Did he think that the Mac UI which did make it into OS X was the "real technology" and that the "kernel" of NeXTSTEP was the entire Cocoa frameworks? In that viewpoint you could say that what Bill Gates said is strictly true, though the result of that-- Isaacson thinking that the NeXT acquisition was a waste of money other than getting Jobs, is pretty deceptive.
Its possible Bill Gates is old and wasn't thinking clearly, or was deceiving himself,, or Isaacson is completely misrepresenting what he said.
[1] Note that to date, Apple has never released a Kindle competitor. It has released very different things, the iPhone and iPad. They do allow you to read books, of course, with iBooks, but Apple wasn't chasing the Kindle, and the question was whether Apple was going to compete with the kindle.