Truthfully, having more cores is really fun and pretty useful, I have no clue how it works in Macs, but in Windows you can set what cores to run a program and that would actually speed up your work. Allowing a number of cores to be doing intensive work while the rest are used for other things. Very useful when you are working in Photoshop, Premiere Pro, and happen to have a CAD program open at the exact same time. Multitasking is a breeze on a 8 core CPU on stock speeds compared to what an overclocked 4 core can do.
However at the same time you have to consider aesthetics, battery life, and what OS you like or are willing to use and a whole bunch of other factors. Price is also a huge factor. For me personally the main points for a PC is familiarity with Windows, price, and fun factor, all while being a pretty OS and how much you can customize. And for Macs (though I don't own one yet) and more specifically Macbooks, is the aesthetics, durability, sound level, and engineering. The Macs are known for how awesome they can be, but even if I got one it would be loaded up with Windows and Linux anyways.
If you love Final Cut Pro so much you should probably go for the Mac, Hackintosh laptops are a pain the the rear end, and performance will be horrendous anyways. If you are going to be gaming or doing things that will specifically not run on a Mac, perhaps encoding with x264 (though I swear there is a Mac version), or want to have a computer that will do literally everything even if there are problems, then go PC. Err... but stay away from Windows 8 if you can... it isn't all that great... I have it installed on a few older Dell Workstations and I regret it, though the driver support is amazing, saved my butt when I couldn't find them.
Of course all of this is my personal opinion mixed with some facts and stuff. I work in Photoshop, Premiere Pro, Solidworks and encode with MeGUI on a regular basis. All while having some interest in computers and the deeper things. I am a Windows person and I stick around Windows 7 and Windows Vista (yes, Vista, it doesn't actually suck that much).
All of this is up to you, figure out what you want your computer to do for you, how much you are willing to pay and how much you are willing to comprise. Then go look at the computers that you can buy, play with them. Then make your decision.
So you like Windows Vista but dislike Windows 8?