I confirmed this with a phone call to Disneyland Resort this afternoon. It's certainly going to change the way some people decide on whether they want to keep buying AP's for their kids:
Disney is making a change to the age of admission policy for all of its US parks, including all the gated attractions at Walt Disney World and Disneyland Resort. Locations included are Magic Kingdom, Epcot, Disney's Hollywood Studios, Disney's Animal Kingdom, Disney's Blizzard Beach, Disney's Typhoon Lagoon, DisneyQuest, Disneyland Park and Disney's California Adventure.
Starting March 23 2013, guests under age 14 will need to be accompanied by a guest age 14 or older. Currently, the policy is that guests under 7 years of age must be accompanied by a guest age 14 or older.