Tweaking reality -- Photoshop turns 20

It's a birthday that art directors and editors will wish to mark -- next Friday is the 20th anniversary of the introduction of Photoshop. The ubiquitous image manipulation software has been used for good in the magazine business (but also for some not-so-good purposes, including cover shot makeovers on fashion and celebrity titles. The example below shows actress Keira Knightly before and after.)