For younger people just starting to build a library I think the value proposition is definitely in favor of eReaders. They don't have to buy or move book cases, they can carry their entire library in one hand, you can re-download all your books in the event of a catastrophe (imagine trying to find and repurchase all of your books if they were destroyed in a fire) -- I could go on.
I'm under 30 and already have 3-4 bookshelves full. And that's after throwing away half of them. At this rate my Kindle will save me a bundle of money and pain.
The vendor lock-in is an annoying issue to some, but it's not an game-stopper for many people.
So, yeah, more expensive than the nominal value of some bookcases but there's much more to consider than that.
(Also, it still doesn't address the principle of the matter: digital music has gone DRM-free, it's time for eBooks to do the same.)
DRM is bound to lose on books. One reason is the analog hole, same as with music. A dedicated hobbyist with a scanner and OCR could easily produce unencumbered e-books even if DRM were perfect. Also, the bits in an e-book are always going to be easy to pirate just because there are so few of them. A book weighs in around a half a megabyte of uncompressed text.
You're not vendor-locked with the Kindle with these tools. Your /brain/ might be vendor-locked though, if you think that a Kindle will only ever read stuff bought from Amazon. I bought a Kindle for a friend, and torrented hundreds of ebooks for her. She hasn't paid a cent to DRM formats. When she wants a new book, she can purchase an ebook from somewhere other than Amazon if she wants to avoid DRM, and use Calibre to convert to .mobi format, which the Kindle happily reads.
Also, do any DRM-free stores have nearly the selection of Amazon/B&N/iBooks? From what I understand, the DRM-free stores only have independent/self-published books.