I'm an Apple Certified Network Administrator - I maintain about 600 systems, of which only 30 or so are not made by Apple.
I find apple to be an interesting concept - but frankly its not worth swapping to! The only advantage of buying Apple vs IBM-compatible is the aesthetic one.
You want secure, hard to find software for, and be in a "niche" market? Get a good system with Windows, reject the terms and conditions to Windows. Get a refund for the Windows Operating system and install Linux.
Apple is safer than Windows? You mean Macintosh OsX? Yeah right. Just look at the last security patches released by Apple. iTunes alone generates enough exploits to compete with Microsoft. Why does OsX not have spyware/adware/etc? Well, it does. Its just MUCH less common as so few people use OsX that its not worth developing spyware for most of the time (but it has been done).
So, if you are choosing a new computer; don't compare Apple vs Windows. If you are "flexible" with an operating system; think in terms of hardware. What do you get for your money. Apple is just another company like Toshiba, Dell or HP.
I'm typing this on a MacBook Pro (2.4Ghz/2GB/160GB)(the ones released 2/3 weeks ago) btw, and have already had to install 3 security patches. The most annoying is the wireless card that drops you off the network every few minutes under OsX as there is a conflict with the drivers. I'm runnign Windows under bootcamp (basically a on-boot operating system selector) and would say that as the hardware goes, the laptop compares to most Toshiba's with similar specs. No better, no worse.
One thing I will FULLY agree that Apple hardware is better at is fireWire. FireWire 400 might be slower than USB2.0 on paper - but USB2.0 operates at 480mb/s only in burst mode. If you are streaming huge files (like a video from a camcorder) Apple is a better choice.
One thing I absolutely abhor apple for is their USB drivers. Take a Toshiba and an Apple. Run nothing but the operating system. Plug in a usb-flash drive and test file transfer speeds. Apple has always had issues with USB and the speeds really reflect this.
Overall; this is how I would divide the operating systems:
Windows: General public, ideal for first time users with all their pop-up help messages.
Linux: Designed for an by people who like to know whats running at any time (this is a generalisation as linux comes in so many different flavours). Ideal if you are computer-savvy.
OsX: Ideal for looks. Perfect for most movies, commercials, and firms that want to make a striking first impression. Software support is the worst amongst the three. (so much so that if you set up an iPod under OsX as a mobile hard drive, you will be able to use it ONLY with OsX - thus making it useless as a MOBILE hard drive.)
I find that I use windows 95% of the time of this laptop - swapping to OsX only when I need to do video editing or image editing.
Hope this helps,
Michele