I tried out Mordor today, and have quite a few remarks. I played with a transferred character, level 105 dwarf guardian running non-raid armor.
I was surprised to find that mobs were immediately much more difficult than in the previous area. Avoidances were way up, my damage was down, and every fight was a challenge to survive. This may be because guardians do no damage anyway, but it was extra challenging and I died multiple times on seemingly trash mobs around the landscape. I am not running endgame raid gear. If Mordor were to go live tomorrow, I would expect many, many, players would be immediately turned off at the difficulty scale. Many people don't have T2C Throne gear, and without it I feel like coming straight into the region is suicide. It will be a necessity to get that 106th level prior to entering Mordor just to make the mobs approachable.
From killing what mobs I did, I did not get a single piece of armor or weapons. Maybe this is a new strategy in Mordor, but in other areas the mobs would drop at least an uncommon item here or there. Never anything worth saving, but still something. I would expect the same thing from an enemy working in a battle camp and forge.
The quest pathing was confusing, cluttered, and seemingly missing. I would go to a place where it said I was supposed to do something, but there was nothing there. Sometimes it was a couple dozen meters off, other times absent (several hatches I needed to open/close were just not there). I ended up just skipping many quests because I couldn't progress them in a timely manner. The locations of signal flags, for example, was not correlating between the map and their actual locations.
The region was a lot more populated with mobs than I expected. I was expecting something like after-battle Osgiliath, where the good guys have defeated the bad guys and the enemy is sparse and running away. But Mordor had many more enemies than I expected there to be after the fall of the Black Gate (especially around Udun and the forges).
These comments come after only a couple hours playing. I did not get that deep into the content, but after that time I was extremely frustrated with my character's performance and the difficulty of killing anything. I plan on rolling a new character up to 115 to see how that changes the gameplay.