This morning Walt Disney World announced that limited park hopping will be returning on January 1st. The new system requires a park pass reservation for your first park of the day. Then at 2pm if you have a valid park hopping option on your ticket you can go to a second park (no additional reservation is required). This was announced via a post on the Disney Parks Blog. The Official Walt Disney World Parks and Tickets: Know Before You Go Page has been updated too.
For a summary of the current Disney Park Closures and Reopenings here is our tracking page.