While this is a topic that could easily (and does often) degenerate into complete misinformation and FUD, NPR basically acknowledges that Macs are showing up in more and more places (and that includes the iPhone, where even Apple is concerned about security), and that means that they're becoming a juicier target for malware developers. Fortunately, however, a familiar voice shows up later in the report (dig those dulcet tones!) to remind everyone that throughout five iterations of OS X, the malware problems have been hard to find. Malware developers may be trying, but it ain't working.
Of course, we can't let this go without noting that this story was inspired in the first place by a PR report released by... you guessed it: an antivirus company. The people who profit off of programs that supposedly prevent malware are claiming that malware is a bigger threat than ever before? Go figure.