I agree with DArtagnan's mini-review earlier in this thread.
I am an old school RPG fan (Wiz VII was the best, MM3, etc.) but I also enjoy many of the AAA games which nowadays have RPG elements but are not really RPGs per se (not getting into a semantics argument). Maybe it would be helpful to compare RPG-ness of games.
Games like Assassin's Creed and Shadow of Mordor have somewhat less RPG-ness than the Mass Effect series (I know I know, that's damning this game right there for some RPG fans) but they are also not "just" action games like Call of Duty. For me the setting and story are very important, so if you take one of these hybrid open world games (or even an RPG) and give me an uninteresting setting and story then I wouldn't enjoy it.
Shadow of Mordor has a very good setting in my view. The story seems good so far but I have only played for several hours, and from the reviews I have read the story is only so-so overall, but even if that's the case the setting and gameplay seem very good enough to make it an overall very good game. Too early to say but so far a big thumbs up from me.