Because so much of the site is based around mouseovers, touch makes the site impossible to use efficiently. Why can't the buttons for edit, quote and reply always be visible instead of needing a mouseover? My computer does have a trackpad and keyboard but I love the W8 touch experience and stuff like this, especially on a new modern redesign, is bizarre. Just putting my two cents in for maybe an update or something.
It's not really a bug per se, but I don't know where else to put it. Tapping on the paragraph intended to be quoted or replied results in nothing so it's kind of a bug.