As long as the publishers have a say, this feature doesn't matter. Don't believe me? Look at the Nook. I've bought over 30 books on it, 2 of them have the LendMe feature. For books I expect to share and re-read, I'm back to the physical copy. The only new ebooks I'm getting are the disposable fiction stories; which is probably the business model Amazon/BN have in mind and why we're still years away from a reasonable…
The more important news, to me, is that they're now going to let you get subscribed magazines and newspapers in the kindle apps. Right now those only work with kindle hardware.