I admit that I did a double-take myself but assuming it's true, follow the money, folks.
Apple would only do this if it thought it would make contribution to its bottom line; I can't imagine the parts will be available at anything other than Apple premium pricing. It also smacks of Apple trying to get ahead of/steer any forthcoming legislation from Washington or Brussels.
And for those who think they can do it themselves and mess it up...well, Apple can't be held responsible for that but will happily sell you a shiny new device (in addition to the part you just paid for/wasted). Of course, after trashing your old device, you might then be prepared to shell out for AppleCare for the new device too. It's a win/win/win!*
Seriously, this has to be a good thing and, especially when it comes to modern batteries, a lot of people will be happier buying a reliable and safe product from Apple.
Now, how to unstick that battery adhesive... ?
*All three wins for Apple.