We're pretty excited! Windows 10 takes the best parts of Windows 7 and Windows 8 and combines them into a single operating system.
For the record, we really liked Windows 8/8.1, but perhaps its Metro/Modern UI (the tiles) were a bridge too far for many. My colleague Charlie, commented that Windows 8x was a little bit Jekyll and Hyde and depending on what you tried to do, you'd either get Dr Jekyll or Mr Hyde! Ever tried to reconfigure wifi in Windows 8? See Mr Hyde.