darren asked me how to adjust the PDF printing compression settings on the Mac, so here's the answer for all...
when you choose the print to PDF option there are a bunch of options below that. eg. compress PDF.
these are actually Automator scripts that are stored in Library/PDF Services
double-click one and it will open up in Automator.
Change the compression settings and save it under a new name in the PDF Services folder. It will be added to the PDF menu when you print.