From Jennifer Fickley-Baker on the Disney Parks Blog:
Under the Sea ~ Journey of the Little Mermaid is one of several attractions currently under construction in the New Fantasyland expansion of Magic Kingdom Park.
This is a very exciting time as various elements are currently being installed in the attraction. Walt Disney Imagineers are currently putting the finishing touches on a sweeping seaside mural that will welcome guests to the load-in area of this attraction.
This video, provided by WDI, shows how Imagineers created an experimental process using digital technology to design the mural, and then used portable tablets to guide them in the artistic process when it came time to put paint on canvas.