I work as a system administrator for an office that runs roughly 70/30 PCs vs. Macs. I consider myself platform agnostic in that I have a Windows desktop machine, a MacBook and an old laptop running Linux (Ubuntu). I'm here to tell you to ignore anyone who makes the blanket claim that one is vastly superior to anything else. Bullshit. Like most brand or platform evangelists, they're all just tools. Pick the one that suits you best and don't look back.
A few additional notes:
1) Anyone who calls Windows a clunky OS probably hasn't logged any time to speak of using Windows 7. It is, in my opinion, by far the best OS Microsoft has ever produced. Most average users won't care, but the fact is there are a lot of system administration tasks and/or features that are considerably more intuitive on Windows machines. Sorry, but that's fact. If you don't believe it, you probably have no use for these, and that's fine. Yes, Internet Explorer is still a big ol' piece of shit, but as far as I'm concerned, so is Safari. That's why God gave us Chrome and Firefox.
2) Macs are great when they're running properly. God help you if you have a hardware problem. Anything more than swapping out RAM means you're at the mercy of an Apple-certified repair facility. They do break. I can't count the number of times I had to haul one in for a problem that, on a Windows machine, would be a $100 part and 10 minutes of my time to fix. Get the AppleCare plan (3-year warranty). Apple's default 1-year warranty is an industry joke. Way to have faith in your product, guys.
3) Despite what the fanbois and fangrrrls want you to think, Apple's upgrade path is far closer to the old Microsoft that Microsoft is now. Snow Leopard and Lion both had some pretty serious bugs and by-design drawbacks from a system administration perspective. Again, most people who aren't configuring these things for enterprise network operations won't care, but them's the facts. Lion is a pretty worthless upgrade that drops legacy support for a lot of older applications (Rosetta is dead for no good reason). If you're starting fresh, you won't really care.
4) In my opinion, the MacBook Air is insanely overpriced. If you want the lightest laptop imaginable, it's your best option. If you need storage space, go with a MacBook. I've seen problems with the Air that I believe are the result of overheating due to 3 pounds worth of shit being stuffed into a 1.5 pound bag. Again, warranty.
5) Aside from screen size and sexy aluminum casing, there's not a hell of a lot of difference between the MacBook Pro and MacBook under the hood. If a 13.3" screen is sufficient for you, you'll save yourself a chunk of change foregoing the Pro.
6) This is the first time I've ever heard anyone describe 1280x800 resolution as "low." Maybe I'm just a cave fish from a bygone era. Frankly, the fact that Apple pulls this crap in an attempt to upsell you to the more expensive model is just one more thing to dislike about the company's current business model. Higher resolution demands more processing power, by the way, so it's a trade-off in system resources.