As someone who came in late on the hype (figured I would wait to bargain this one) I wanted to share my thoughts for anyone one the fence. Hint: HOOK IT TO MY VEINS!
To start, the game looks great and runs extremely smoothly so far. Seems like devs are finally starting to hit their stride with the new systems. Ive only been in one part of the world so far, but Mordor actually looks cool and is dreary but not boring which had worried me.
The story seems like it is going to be standard revenge fair with some super Gollum / Celebrimdor mystery mixed in. The real madness is going to come from the nemesis system, which I will get to.
Ive only just started, but the combat is super smooth and intuitive but not easy. I typically start off by scouting areas and picking off archers / ranged guys with my bow from distance and then using structures, bushes, and etc. to stealth takedown as many orcs as I can. It is also awesome to blast open a cage with a beast in it and watch them just rampage through the camp doing your job for you. I also unlocked a skill to ride the beasts, but have yet to pull it off. Once you get into a close fight it basically becomes a mix of pulling off stuns, counters, hits, dodges, and finishers. Very fluid and very fun.
Traversal works quite well too. Pretty much if it seems climbable / jumpable it is, and you really do want to stay above the fray a lot or you will get swarmed.
Now for the best part. The nemesis system is amazing and it is going to ruin games that dont have similar interactive depth from this point on. As you battle the orcs and uruks you can interrogate them to learn more about the leaders and their hierarchy which is all shown via a sort of chessboard menu. You learn their ranks, strengths, weaknesses, alliances, and etc. which all plays out as you play. This captain is immune to stealth and ranged weapons but afraid of fire? Wait till he is near a fire and explode it then watch him panic and dominate. Get owned by an orc and die? Next time you see him he will literally smack talk you about how he dominated you. Or if you meet someone accidentally in the open world and have to flee because you are overwhelmed, they will talk about how you are a coward and they will gain rank amongst their army because they drove you off.
Long story short, what you do is actually reflected in the game world instead of the typical static world with you in it (think guards talking about how dragons possibly coming back in Skyrim right after you slay one in front of them).
A lot of the new franchises have been launching with potential this gen, but just sort of falling a short. (Destiny and Titanfall are both a blast but lack content and variety), but Shadow of Mordor is out of the gate sprinting.
TLDR This is exceedingly fun and feels like the world is actually reacting to you!