Looking at their gameplay demonstration it was still possible for a character outside combat to...
a) move around as much as they wanted without being pulled into turn based mode
b) sneak up on enemies without having to do a Stealth check.
What's with not using the actual SKILL for sneaking? Why is someone with -1 and Disadvantage on Stealth as good at sneaking as someone with +14?
Even though Hide might be an action now, Rogues can still attack and BA Hide. And Rogue would be the exact class I would play sneaky with. So it can't be a broken "I win" button.