From F-Secure advises against using Adobe Reader article:

Of the targeted attacks on managers, politicians and other high-ranking individuals registered this year, almost 50 per cent have exploited six security vulnerabilities in Adobe’s PDF products. In 2008 it was Microsoft Word which proved the most popular target – with 35 per cent – for such attacks, although the number of vulnerabilities in Adobe Reader (19) was already exceeding the number in Word (15) by four. Hypponen notes that while the number of infected PDF files observed between January and April 2008 was just 128, over the same period this year it rose to more than 2300.

So, you have been warned ;). And just to remind you (though you’re probably aware of that):

• New Technology Removes 40-bit Adobe PDF Encryption in Minutes… Guaranteed
• ElcomSoft Claims Adobe Acrobat 9 Is a Hundred Times Less Secure