Hello archdruid.
Photoshop is one of my tools for working with digital art projects.  My other tools are Adobe After Effects, Cinema 4D, and Vue, to name a few.  In the past I have used Photoshop for post touch up work on 3D rendered scenes. This year I'm going to spend some time in exploring raw digital drawing / painting (art without the aid of 3d tools providing a base) with photoshop and Illulstrator.

So if you or anyone can point out what Corel Painter can offer in this area (raw digital drawing / painting) that would make it worth it to add it to my other tools then please do.  I am going to see if I can download Corel Painter today, hoping if I can find out as well but like most mature art products I suspect it will be filled with a huge list of features which will take more time than the trial period will provide to uncover.