It's still in the late stages of development, but ImageNest looks like a very promising app for Mac users who need page layout capabilities beyond what Lightroom offers. Like the nesting features of high-end RIPS, you can gang up multiple images on a sheet at different sizes, rotate, scale, crop, print trim marks, etc. There's full support for ICC profiles (both source and output). It's scheduled for release in about a month. I hope to get hold of v1.0 fairly soon.