This update should make plenty of designers and photo editors very happy.
The higher resolution of the screen means that all bitmapped application elements, including toolbars, buttons and application chrome need to be redrawn and recompiled for Retina displays. Retina support for Photoshop required the replacement of more than 2,500 icons and cursors. What’s more, supporting HiDPI screens presents its own set of challenges for applications that support bitmaps and vector content.
Today, Photoshop and Illustrator users will get the update.