In my personal case, it is a mixing feeling situation.
Lets start with the positive side: the speed; in fact is almost a hardware improvement due the embedded processor overclock, and speed is always welcome!
The interface is a way better, more readable and comfortable.
The smart thing that when you install apps from the app manager, it remembers your last selection.
Better WM streams capabilities
Negative side/suggestions:
"Right clik" does'nt always locks in position
Drag and drop doesn't always works..(sometimes you need several attempts to get the things done)
The "fingers keyboard" issue
I don't understand why there isn't an easy way to add/delete icons on left side of the desktop (contacts, web, etc) I've found some "dictatorials aspects" here, p.e. you can´t easily get ride of the Raphsody thing. You can only remove empty folders when you are rearranging folders (?)
Don't understand also why you can't put folders' shortcuts on desktop. (Is there a way to do that?)
Nice would be if the Nokia update wizard let you to select when you want to install the OS and apps (I mean be able to install the OS on Internal-external card whe flashing). That will be and easy, non scary process for those "normal" users that don't will to play with fire thru the dual boot installation procedure.
Not complete WM streams capability, still some of them works, some others not.