We know that Monolith never hinted that they were going to work on the sequel to Shadow of Mordor but what most people believe that a sequel was going to happen based on the ending of the first game.
There was also the time when the game was spotted in the resume of a stunt actress. However, things got very quiet after E3 where the game was not announced. Everybody thought that they would hear more about the game at E3 but that did not happen.
It has been so quiet the last couple of months that we are starting to feel like the game might not be happening. Previous rumor suggesting that the Shadow of Mordor 2 might be coming with a bigger map. The developers also said that they were looking to do more with the Nemesis system so we should see the system come with more features.
Fans were also hoping that they will be able to get out of Mordor this time but we do not think that will happen. The name of the game is Shadow of Mordor after all.