I'm a hybrid user. Native OSX software is available for Quark, Adobe Photoshop, and Adobe InDesign. I prefer my PC but mainly because that's what I grew up around, and consequently the vocabulary surrounding PCs makes more sense in my head. I'm not a gamer, so I have no input there. But having used both Macs and PCs to design ads, both get the job done. From a work perspective, it's valuable to know both formats. It makes you a more flexible employee, and potential employers can spot that.