I installed the preview,
I played for a few hours. For me it offers nothing over Win 7 that would make me want to use it. And a whole lot of "features" that make me not want to use it. Each to their own and their own needs, I don't need Windows 10.
Seems to be Windows 7 with a big start menu, except the system settings are harder to find. And every Microsoft service available is forced down the users throat. I think MS want the OS to be used the way THEY want the user to use it. Not going to happen here.