I'm running win 8 on a new touch screen laptop and haven't hated it. I do find I spend most of my computing time in the desktop UI though. If I was trying to navigate 8 without the touch ability it would be a pain in the ass. My biggest gripe with it though is the way the tiles are layed out. I haven't been able to figure out: how to group tiles I want, get rid of tiles I don't want and add the tiles I do. I figure it's probably easy to do this, I just haven't taken the time to mess with it.
Win 8 does run and boot quickly, but still seems to rely significantly on the desktop UI. With the heavy reliance on the desktop UI, not adding the start button is a mistake. That being said, I believe Win 8 is a transitional OS to allow the phase out of legacy software and the next windows will likely not be backward compatible while completely phasing out the desktop UI.