Guillermo del Torro was going to do a HM film, and HBG was going to be featured prominently in it. They released some concept art, and this ghost's animatronic face looks exactly like that concept art, down to the gold tooth (view the YouTube video in HD full screen to see the gold tooth):
Though maybe the original HBG had a gold tooth as well:
http://www.doombuggies.com/myths2.php Some photos here.
All indications are that he is looking for a writer to work on the script, and that Disney is interested in the film:
I’m such a Disneyland fanatic. I need to get an update on what’s happening with Haunted Mansion.
Guillermo del Torro: Yeah, we are still pursuing a writer that is very hard to get. We are meeting with them. The problem is I don’t want just anyone to rewrite the screenplay. I wrote the screenplay with Mathew Robbins and I really want somebody that will bring a lot to it, but Disney is aching to make it and I’m aching to make it. If we could… If you know of anyone who can write, because I’m only going to produce it, I would love to hear.
From --- /Film Interview: Guillermo del Toro Talks â€˜Pacific Rimâ€™, â€˜Haunted Mansionâ€™ and More | /Film July 12, 2013
So, maybe an HM film is in the works!
I think they could fit a Pepper's Ghost effect in the attic scene, which I think is one of the best ways to do this trick.