I've encountered the bug too. I use the most recent version of Mathematica with Yosemite. When I print to PDF, and then view the PDF in Preview, the plots are messed up but, interestingly, they are fine in the thumbnails. But there is another problem with Mathematica's PDF that is worse. When I print a hard copy of a PDF, it prints fine, even the messed up plots, but when I email one to a Windows user, they cannot print it at all. This has happened with two Windows users, and I have confirmed that they are able to print other non-Mathematica PDFs that I create and send to them. I've attached my buggy PDF if you care to look.
How can I contact Wolfram to report the bug to reinforce what you have reported? I too hope that Wolfram will fix the problem soon because the current CDF Player is incompatible, i.e., dynamic things like Manipulate, with the newest version of Mathematica, and without the PDF engine broke, I am struggling to share documents with my students, colleagues, and clients.
Sincerely,
Gregory
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