That's exactly the case, unfortunately. With Metro you say "bye bye" to multitasking and 'windows', which is crazy for a Desktop OS.
I installed the customer preview version and using it was really terrible. I even tried to get used to it, thinking that I was simply whining and that I'm getting afraid of change but no, it's simply hands down the worst Windows version for its time. It kills productivity. I don't mean only "work'. It's really hard to use it for work but it's also hard to do anything if you like doing more than 1 thing at a time on your computer.
Microsoft are fortunate that Windows 7 is still good and most people will be fine using it for another year or two. If it wasn't the case Apple would happily gain a lot of new consumers coming from Windows. Heck, Windows 8 makes a lot of people jump to Linux already. Including companies, even video game companies (Steam).