"My computer has never crashed, and my software rarely crashes. Of
course, all this has to do with a little computer maintenance and proper
media management. I'm sure there are PC users out there who don't
experience crashing either."
Sound advice indeed. Mac's and PC's except for a small group of manufacturers use nearly all the same components these days. The only real diffs between them are the OS code and the fact that it is legal to build your own PC and highly frowned upon (if not illegal) to build your own Mac. The same advantage you get from buying a mac is the same one you get from buying from the reputable pre-built PC companies like HP (not Compaq), Dell, IBM, Toshiba and a number of others in that you get comprehensive support (provided you pay for it) in addition to brand name quality.
Now as to your question of an 'apple rig with FCS or CS5 on it' I would have to say you'd come out cheaper with the all apple set up (God what am I saying?) Though I feel Adobe products are far more comprehensive and superior in many aspects (however apple color is to be contended with in addition to final cut), CS5 will be much more expensive.
To take advantage of the many innovations particularly the GPU supported rendering, you'll need a rig with some real horsepower. Right now there are only a small number of GPU's supported for the Mac and there is only one relatively inexpensive one (around $800+) the rest start tippin' the 'scales' at $2k. That and you'll need a minimum of 8GB of RAM (faster the better) or more (most machines in the reviews I've read had 16GB of RAM.) Beyond the 8GB mark, RAM really gets expensive and you will need a machine with a motherboard capable of handling larger amounts of RAM to get the full bang out of Premiere and AFX's new features.
Now, if you were building your own PC you could work your way through that with only a small amount of 'hemmoraging' from your wallet. Since you're talking about buying a Mac with similar capabilities, you're going to spend a lot of money just for the basic system that you could do your own upgrades with. Fuggeddabout how much you'd have to hork up if you let apple make the thing entirely. Yet, if you have the work coming in that will justify the cost or if you're one of those hideously lucky 'trustfund babies' and can throw fistfuls of cash at it, knock yourself out.
Funny thing is, you're going to end up buying Adobe products anyway. Few in this industry don't have a copy of at least Photoshop on their systems.