Are you looking at them with adobe reader? For some reason it displays awfully, 100% is nowhere near the real 100%, you need to zoom to approx 250% and even then it's not a real 100%. I hate this limitation. Open the pdf in CS5 and you will see it's fine.
I'm looking at it in Apple's Preview pdf viewing software.
I ditched Adobe Reader a year ago because of its poor user interface.
I send my pdfs (treatments) out to all kind of people involved in a shoot (hair, make-up, wardrobe stylist, model agency), therefore it bothers me that they can't see it as in as high a quality as it was created in.
But, basically, your message is: it's not the Bridge pdf creation, it's the viewer software that is bad.