Just some updates from what I have read:
1) The old dock cannot be used with the new tablet.
2) The tablet + dock is the same thickness as an ultrabook!
3) The weight of the tablet + dock is about the same as an ultrabook!
4) The battery life is about 9 hours non-stop playback of HD videos and wifi on. Likely to be over 12 hours (as promised by ASUS) for non-CPU intensive use.
5) The dock's keyboard is very responsive unlike the previous version.
6) The tablet is still heavier than the dock, and when attached, there is still a tendency for the tablet to fall over backwards due to its weight.
7) No USB ports on the tablet, only on the dock, only USB2.0.
8) No 3G dongles can be used on the tablet unless you root the tablet.
9) No 3G version in sight...
10) The old Transformer will be sold alongside the new one, but for a lower price.
11) The Tegra 3 system can take some game controllers, made mainly by Logitech apparently, as well as standard PS3 controllers, XBox and a few others.
12) Very few apps are optimised for 4 cores, so only the games that are bundled with the tablet make use of the 4 cores and show those fantastic graphics. Not indication that the quad core will run your usual apps faster visibly although the UI is visibly smoother than before. That is on 3.2 and current tablets, when scrolling in the Android UI, there is a tendency to lag or sudden speed ups, unlike iOS. Apparently, this is no longer an issue with the Tegra 3 processor for 3.2.
Yups, this is all I gleaned so far on reading the net...