I think the idea of reading books on a DS sounds ... weird to me!
Why would anyone read books on a small screen, and have a heavy device for that?
Plus, the battery life isn't as great as the e-ink devices....
It'd be nice if you could browse online with it,reading books.
But probably you'll need to buy a $20 disk in order to read 5 or 10 books (which you can get for free from this site).