based on what's currently announced ... I wont get a Nook. It's great that it's android based, but the Nook and the Alex are basically just a Kindle, with the keyboard being replaced by an LCD touch screen (for virtual keyboard, android apps, etc.).
The MUCH more interesting device, IMO, is the Entourage eDGe. Two panels (e-ink with stylus support, LCD touch screen), 10" panels, 360 degree hinge (ie. can fold the panels to be back to back), full Android app support on a 1024x600 screen, etc. Sort of like a Microsoft Courier, but with a real OS. Oh, and support for various e-book formats (possibly also for the nook e-books). Support for virtual and bluetooth keyboards (maybe for usb keyboards).
An Apple Mac OS X (not iPhone) based 10" tablet might be more enticing, with Amazon, Nook, and open E-book formats. Especially if it has the pixelqi hybrid display, and multi-touch, SDHC card slot, SSD options, LONG battery life, support for virtual, usb, and bluetooth keyboards/mice, and display port.
But, if Apple doesn't release an AMAZING 10" tablet in January, I'll definitely be buying the Entourage eDGe in February.
The dualbook one is just giving me a conflicting feeling. It looks like it's a good way to go for getting an e-reader/tablet/netbook hybrid but at same time, how comfortable is it to hold it like that? Yes you can fold it, to read books and stuff but is it really comfortable with that thickness?
The future has to be a hybrid screen, the pixelqi. Apple has a chance to totally not only overtake the tablet market but also ebook readers and netbooks if they include a pixelqi screen that's high quality with multitouch and OS X. It will be worth 800-900$. I would buy one right away. I am sure Apple will take advantage of the same battery that's in MBP.