Saw this yesterday. I would have to say it is the weakest in the series. Quite frankly not even a Die Hard movie, but a series of action sequences that Bruce Willis maneuvers through. No catchy tag likes, yipi kai yea were present. The plot looks like they had a bunch of cool action scene ideas dreamed up that could happen in Russia, and then try to come up with some way to go from one to the other.
If you like watching a random series of things blowing up, John and son running from fire, etc. this is the movie for you.
There is a very good reason this movie was released in February and not December.