Is the Kindle DX Worth the Money?

An anonymous reader writes "Now that some little time has passed, and the hype has died down a bit, I'm wondering if anyone has taken the $500 plunge and gotten a Kindle DX. From the academic-paper-reading-geek perspective, is it worth the money? How well does it work with PDFs, and is it easy to get them on and off? I haven't been able to find any good reviews on the interweb that address its usability as I would like to use it."