Multiple materials on a specific shape? Using cycles, how would I go about making text that is UV mapped onto a surface (in this case a book cover) have a gloss while the remaining part of the image stays matte? The text needs a kind of foil finish with the white being matte paper. Can the mesh be selected with the image, or is there a better way? 

Here's the image in question.
Use your image to control the mix between a glossy and a diffuse shader: