as for the product codes and battery discrepancies the
sony.co.uk site lists the battery life as 6800 page turns. And the play.com specs cite 7000 and 6800 so I believe this must just be a matter of the 'approx' factor.
As for the .CEW tag on the end of the product code. I think that this is a code to say that it has been bought from the SonyStyle store. Upon adding products to the cart, when you checkout, it seems all items get some tag added to the end of them to signify this.