Amazon has just released the Kindle DX with Global Wireless and it's the the same $489 as the previous version. Unlike the confusion that ensued with the release of the Kindle 6" with Global Wireless, Amazon has immediately marked the US Wireless version of the DX as an obsolete item, pointing you to the newer version and listing only used or refurbished options otherwise. Currently there are no refurbished DX's available and the used units start at $589 (the original Kindle listings are nearly as bad, with the only unit under $200 being one with a cracked screen, which presumably you would then use to try to get a $99 refurbished/replacement Kindle direct from Amazon).
The official shipping date for the newest Kindle is January 19, but orders are being taken now to reserve those earliest units. If the past is any indication, those who pay for overnight shipping will get the ones shipped the very first day, as will perhaps be those who pay for 2nd day shipping. Picking standard or Free SuperSaver shipping will result in a later shipping date (even though you ordered earlier than others than choose the faster shipping method). If you want to be one of those with a bright shiny new toy on Martin Luther King's birthday or any time that week, I'd recommend you pick one of the faster methods. Also, if this is your first Kindle, they ship in clearly marked boxes and it's not the kind of delivery I'd want my postman to leave balanced on top of my mailbox (especially if it is raining).