A step in the right direction, in as much as the academic publishers seem to be completely inept a developing a proactive e-publishing strategy when left to their own devices. Given that their books usually have small audiences spread across the world, you think they'd have been motivated to do something about this themselves some time before now (no, I'm not bitter about paying high postage for delivery of expensive print texts from overseas...)
Yay for Amazon for giving four big academic publishers a boot in the pants.
At the same time, I hope that when the other academic publishers - the ones that publish most of the stuff that interests me
- start to take e-publishing seriously, that they choose to publish in a format that isn't linked to a specific device, and that they don't lock the distribution down to a single retailer.