Everyone that despised the new use of the windows key introduced by Win 8 can rest easy in windows 10. Everything I appreciated about the charms launcher is now integrated back into an amazing start menu which feels very intuitive and useful for non-touch screen systems. Where Win8 felt like it was trying to make a touch-interface-centric design reasonably work for a non-touch screen setup, Windows 10 has touch or non-touch modes. In Win8, the quickest way to shut down a system was "windows key - I" which pops out a right sidebar with a power sub-menu. Not very intuitive for users new to windows 8. With 10, it brings the power menu back to the more friendly start menu where it used to be, and although there are hotkeys to do this even more quickly, new users in general will find windows 10 to do essential tasks with less of the learning curve that was inherent to Windows 8.

http://davidreidy.com/windows-10-best-windows-so-far/