So I'd venture the following:

1) In the next three years Amazon will not remove any already sold products on the Kindle due to copyright concerns. 87%

2) In the next five years Amazon will not remove any already sold products due to political pressure. (95%). (This is one of the vaguer ones but I think it should be clear.

3) In the next five years Amazon will not remove any already sold products from the Kindle because the product has been determined to be libelous or blasphemous in some jurisdiction. 95%.

4) In the next five years Amazon will not remove any already sold products from the Kindle that date from before 1920. 99%

5) In the next five years Amazon will not remove any already sold products from the Kindle. 80%.

6) In the next five years Amazon will not remove any already sold products from my Kindle. 98%.

7) (Most relevant to this discussion). In the next five years Amazon will not remove any already sold textbook or copy of a scientific journal. 92%.

I'm willing to make 5-10$ bets on any of these claims at these odds.

In all these cases, the relevant way of testing will be media reports of the removal of the texts, or in the case of 6 by self-reporting. Obviously there's some overlap between some of these predictions. But they seem to be pretty decent estimates. I've focused on media reports because that seems given how much the last issue came up that seems like a safe way of separating the substantial and insubstantial accusations. I've focused on the Kindle primarily because I know more about it than the other e-readers but similar estimates would apply for the others.