What is new? It's multitouch, like their simpler Bamboo models. You can use multitouch gestures in OS X and Windows using your five fingers (like zooming in and out, rotate, pan, or navigate through apps) which is a great addition, all while still being able to use the pressure-sensitive pen. The Intuos 5 actually differentiates between accidental touching and actual user actions. With the Intuos 5 you can actually ditch your mouse or trackpad completely. It just works.
The Intuos 5 retains the same fine sensitivity as the Intuos 4: 2048 levels of pressure, requiring only 1 gram of pressure to start painting. Gone are the built-in LCD displays, replaced with an onscreen HUD that appears when you smoothly put your fingers over the capacitative buttons. It's a good change. It actually makes more sense to summon the HUD on command without having to take your eyes off the screen rather that looking down to the tablet.
The tablet frame is rubberized and, while the actual drawing area remains the same, the surface has been extended. Overall, that feels better than the Intuos 4.
Gone is the Bluetooth, however, replaced with their (optional) wireless module. Wacom says that their Windows clients were having problems with Bluetooth and decided to offer an optimized wireless module to anyone who wants to have wireless capabilities.
The small, medium and large sizes are $230, $350 and $470, respectively.
I'm trying it right now and will post a full review soon. [Wacom]