Stealth

So yes... the "visibility gem" system has been replaced.  Originally, your "hiddeness" effected the probability of an enemy NPC dice roll turning up as 1, and if the dice turned up as 1 then he would see you and give chase.  Sounds good on paper, but in reality this system ended up being far too unforgiving to be fun.  In fact, I don't think I've ever played a game with a "random roll" stealth system that was fun.  Morrowind is a perfect example: there's no way to recover from being seen, and at anything other than higher levels its almost impossible NOT to be seen.  Because it's all based on dice rolls.  As long as you're within an enemy's view range, it's completely random whether or not you are seen.  So in other words, stealth is useless unless you have an ungodly high level, because there's no way to use skill or strategy to ensure that you won't be seen.  To a certain extent, the original Swamplands stealth system was a little like this.  You it was too unforgiving, which is odd to say for a game that is SUPPOSED to be unforgiving.  But still...

Now, we have a system more akin to the one in Far Cry 1.  You have a bar at the top of the screen that shows how close enemies are to spotting you.  Your "hiddeness" determines how fast the bar fills.  Stealth is not easy, but it's possible.  And it feels a lot fairer, since you get a sense of whether or not you're hiding well enough without immediately failing.  And, there's no randomness.