Despite his declarations of interest, Viggo Mortenson tells Movies.com that he had not been approached to reprise the role of Aragorn for The Hobbit films. Considering filming is at least a third of the way through principle photography, it does seem like he would have been approached by now if a return was planned.

Movies.com: Has Peter Jackson asked you to return to Middle Earth in the Hobbit movie in any capacity?
Mortensen: At one point, the producers asked if I would do it and I said sure if Aragorn is supposed to be in the bridge story because he's not in The Hobbit. I would rather do it than see someone else do it, but I've never been asked and they're shooting the movie. I'm not in it unless it there is some last-minute plan they have, but I thought I would have heard of it by now. Orlando Bloom and Cate Blanchett shot something, but they're elves and don't change as rapidly. As you know, Aragorn is half elf and also lives a couple hundred years or more and he could be in a bridge, but I have to assume it isn't going to happen. That was an important period in my life and I will always be grateful that the trilogy was so successful and gave me a lot of new opportunities. I never would have gotten A History of Violence, no matter how much David wanted me, had it not been for my newfound notoriety.

The character was alive at the time of The Hobbit but was not actually in the novel but then again neither were Elijah Wood, Cate Blanchett, Christopher Lee, Orlando Bloom, and Hugo Weaving. While it is possible Peter Jackson is leaving this as a surprise, more than likely he just doesn't want to deal with Viggo Mortenson. The actor has a bit of a repuation for being a touch difficult on set and often led the charge in many of the legal suits that plagued the trilogy once it became a huge success. (via TOR)

Aragorn Not in The Hobbit. There are any Aragorn Not in The Hobbit in here.