[muyuu]

Most designers I know will draw on illustrator and maybe finish up in Photoshop. Since Photoshop is a sort of common baseline in the industry it's used as a general tool to aid in the finishing of artwork even when said artwork is not really in its domain.

[ehurrell]

Illustrator seems widely used in brand and web design alright, but for example concept artists and comic artists I know never leave Photoshop, start to finish.