The new interface is cartoonish, inconsistent, awkward to use, complicated to find the simplest things. Case in point, I had to do a google search just to figure out how to turn off my PC (turns out it's several obtuse steps involving going into Settings rather than 2 simple ones). If MS meant for this to be intuitive and simple, they've failed miserably. If I had trouble as a software engineer for over 20 years, how is the general public going to fare?
It fails as an HTPC interface on a very basic level. No matter how you set the font or icon sizes, it's nearly impossible to read the text from 10' away. The simplest tasks often require a text search. My family and I need to be able to operate an HTPC with a remote for the most part. Text searches for launching programs or changing settings is unacceptable. A modern OS should make it quick and easy to navigate to an icon or menu item to perform a given task . This is simply impossible on Win 8.
My young son literally laughed out loud when he first saw Metro. He though I was playing a joke on him. When I convinced him this was really Windows 8, he was very depressed as I was. It's actually very sad that this is going to be the future of computing.