Walt Disney, the media and entertainment group, put animation back at the heart of its strategy when it announced the $7.4bn (£4.1bn) acquisition of Pixar, the company behind Finding Nemo and Toy Story last night. The all-share deal makes Steve Jobs, the head of Pixar and founder of Apple computers, the largest single shareholder in the theme park and media group with an estimated 7% stake. He also gets a seat on the Disney board.