It partly depends on what you expect to use your computer for. If you're going to do more media-related things (especially things concerning video and video editing), I would recommend that you get the Mac. I majored in Film and Photography Studies in college, and all of my video and multimedia classes made use of Macs. When I edited video in college, I used FinalCut Pro on a Mac.
On the other hand, if you're going to use your computer primarily for word processing, document creation, surfing the Internet, etc., I would buy a PC. I would recommend a Dell. I actually have 2 Dell laptops (I got a new one for Christmas last year, in fact), and the older one, which I've had for about 6 years now, and use pretty much every day, still runs perfectly! I've had no problems with it whatsoever in all that time.