So I think I stumbled upon an incomplete version of the Haunt website, and it's quite interesting. Amazing how you can move around an incomplete website with Google. I say it's incomplete because it still says at the top "new in 2014" and mentions Maze of Madness as a new maze. But the rest of the items say that they're new for 2015. Guessing the full site will be released within the next week.
For one, the Overlord is returning (super glad to hear that). A new show called "Unstrung" is coming, which basically sounds like the puppets. The new maze taking Outbreak's place is called Lockdown and Blue Ridge Bloodbath has been changed to Tollway Terror. I've provided the link below, along with descriptions of the two mazes and new show.
Haunt Website
Unstrung - The battle lines have been drawn and the outcome is unknown. Join us for this all new, multimedia infused production unlike anything ever seen at the Kings Dominion Theater. In this tale of oppression and suffering, will the Puppet Master regain control over his dolls or will they succeed in overthrowing him? In the end, who will become Unstrung?
Lockdown - More than half a century ago an infamous riot claimed the lives of dozens of men at Doswell State Penitentiary. Following the massacre, the prison was abandoned and left to crumble. Today the prison is finally being reopened and you’re the first to get inside. All visitors are encouraged to stay on the marked paths, or you may find yourself the next victim of this never-ending Lockdown.
A prison theme was mentioned before as a rumor, so good call on that. I think this one will be pretty cool and a big step up from Outbreak. Looking forward to it.
Tollway Terror - Take a drive on the beautiful Blue Ridge Parkway and experience the sights and sounds of the mountains after dark. A warning to any outsiders: According to local legend creatures lurk in the woods at night, rumored to prey on drivers who take a wrong turn. Sit back, relax and ignore the screams of other visitors as you take a ride on the Tollway Terror.
Not sure how this will be different from the old theme of Blue Ridge Bloodbath, but interested to see what they came up with.