I've been incredibly happy with Corel Painter 12. Started using it 5 months ago. It seems, to me, the most "traditional art technique." Especially for pencils, oils, watercolors. And the tracking window is such a huge convenience.
A friend showed my work to someone the other day, who then ran out to buy a wacom and corel, so I guess she liked what the program could do, haha.
I tend to find Photoshop works great for graphics and digital manipulation, but it's not as intuitive for drawing.
Never tried Artrage, though.www.joeyelkins.com