It isn't locked down at all. You can read ebooks from o'reilly, baen, pragprog, and many other non-Amazon stores on it right out of the box.
It simply doesn't implement competing DRM schemes.
EPUB is not a competing DRM scheme. It's the standard for virtually every other reader and store, and the kindle doesn't support it.
Which is a completely separate issue from the claim that the kindle is a locked down device that can only view content bought from Amazon.
In my experience, every DRM-free ebook store I've dealt with has been happy to sell me a .mobi.
Still, the reason they doesn't support epub is most likely because it would make it easier to get books from sources other than amazon. The OP was finding it regretable that they have the motivation to do things like this.
Conversion between (DRM-free) EPUB and MOBI is pretty much trivial. It's a pain, but it's hardly a problem.
Download Calibre to manage your ebooks. It makes conversion pretty much transparent, and with the right plugins you can set it up to remove the DRM from the books you purchase.
Re:Free Kindle This November
by epubdrmremoval on Wednesday March 02, 2011 @03:11AM
(#2278845)
Why not get a professional epub drm removal software here:http://www.removedrmfromepub.com
Speaking of rooting/jailbreaking, I put together a simple guide for those who want to jailbreak their Kindle and use Luigi's standalone terminal:
There is alternative firmware:
http://www.mobileread.com/forums/showthread.php?t=105847
I'd rather pay for it up-front and actually have an open e-book market on the back end. As opposed to having to root/jailbreak it and/or go through painful file conversion processes to read other e-books.