That's the VATS critical thing.... using VATS charges up a meter. When it's full, you can execute a crit in VATS. No details as to whether that overrides the hit%, or anything else.
As for out-of-VATS crits, or sneak attacks... no confirmation of anything yet. But I can't imagine them not having those things.
(Thinking about it, this is one of those awkward intersections between "stats-based" RPGs and action games. In stats RPGs, you get sneak attacks by entering some sort of stealth mode, avoiding detection, and then attacking - frequently from behind. Because it's not direct player control, all these things - like aiming for a weak spot - are covered by game mechanics. In action games, you get special attacks by.... actively aiming your shot at a weak spot. Like the head. Beth games, being in between those two styles, have a bit of both. Manually targeting lets you shoot vulnerable spots, but you also have the "RPG game mechanic" of bonus damage for Sneak Attacks.)