So far, it does NOT appear that Win-8 is a whole new concept. What it looks like, to this old tech, is that they have (maybe) listened to their public and have addressed the BAD parts of Win-7 and tried to FIX them. For the most part, what works for Win-7 also works for Win-8, especially hardware drivers.
Programs that require the dot net framework can fail to work properly or just refuse to load.
I had to install dot net 2.0 before I could get one program to load.
Then and only then would dot net 5.1 install.
At least in this DP version, they have seriously reduced the "Bloat" that was so apparent in Win-7, with the result of an OS that installs quicker, takes up less space on the HD and runs faster.
I had a version of XP called "Stripped to the Bone", that would load in about 15 minutes. Win-8 somewhat reminds me of that old OS.
It will be interesting to see what they add for the Beta version. (all of dot net framework, I hope)