Aside from the price, the biggest strike against the DX is a competing product from Apple. In early 2010, Apple announced that it would release the iPad, which offers a full-color capacitive touch screen that's the same size as the Kindle's monochrome e-ink screen along with a far richer feature set, including much better support for PDF and image files (the iPad also supports video playback, Web browsing, and iPhone apps).
Obviously, in light of Apple's announcement--and the fact that the iPad's $499 starting price is so close to Kindle DX's--the DX becomes much harder to recommend, despite some positive attributes. We expect that Amazon will have to lower the price significantly for the DX to continue to be a viable product.
To get a deeper dive into the Kindle DX, check out our earlier review of the U.S. Wireless version.
Note: Those planning to travel outside of the U.S. should be aware of some caveats. First off, only some countries have Kindle-compatible wireless coverage. And even if cellular "Whispernet" service is offered, additional fees--anywhere from $1.99 per title to $4.99 per week--are charged for books and periodicals downloaded outside the U.S., at least for U.S.-based Kindle owners who are traveling abroad. On the bright side, those using the Kindle internationally can still download sample chapters of books at no charge. (Surcharges can be avoided by downloading Kindle content to a PC first, then transferring it to the Kindle via USB.)