Whether you're a dyed-in-the wool Mac fan or Windows 'til you die, you have to admit that Apple OS launches lack the hysteria of Microsoft's infrequent blowouts. There's already little we don't know about Mac OS X 10.5, or Leopard, and a good thing too. And thanks to the joys of dual-booting, there's no reason why a healthy Mac market shouldn't be good news for Windows.

Apple doesn't make a Microsoft-style song and dance about OS upgrades because it isn't such a big deal. Mac OS X is revamped relatively frequently, with each iteration being more of a refresh than a revolution. And as there's only one hardware manufacturer to consult, there isn't the same Emperor's New Clothes-style rush to hype the software (to flog the hardware).

Never the less, Apple will expect an upturn in its already buoyant Mac sales. But since the advent of Intel-based Apple Macs, this isn't something Microsoft should fear. In fact, unreconstructed Apple fanboys may represent that rarest of things for Windows: a potential fresh market.

Increasing numbers of people are using applications such as Apple's own Boot Camp to run two operating systems on one Apple Mac. Boot Camp's free with Mac OS X, but it requires you to boot into and out of each OS. Parallels Desktop 3.0, on the other hand, lets you run two (or more) operating systems in separate windows on the same desktop.

Now why would anybody want to choose between Windows, OS X and - yes - Linux, when you can enjoy the stability and clean lines of Apple's OS, and the infinite number of programs available to Windows, on the same machine? (And then chuck in Linux for good measure.) Apple sees dual-booting as a way of pulling in long-term Windows users, but there's no reason why the process shouldn't work in reverse. A Mac user could pick up a copy of parallels for £35 and Vista for £99. Not a huge investment on top of a £1,699 inc VAT Mac Pro, say.

Certainly, Ben Rudolph, director of Parallels manufacturer SWSoft, thinks Leopard is good news for his software. He said: "Friday’s launch of Leopard is a big step forward for Apple and should be a further boon to their already exploding sales. Apple always does a great job with building a very consumer friendly OS, and Leopard definitely follows that trend.

"I’m particularly excited about core features like Leopard’s top to bottom 64-bit architecture, and new user-experience features like Stacks, which should help me organize my incredibly messy desktop, and Spaces, which already works great with Parallels Desktop. It’s really cool to be able to work with 2 more OS’s, all in full screen mode, each in a different Space.

"We're confident that Parallels Desktop is compatible with Leopard. Performance is great, and core functionality works smoothly. You'll be able to safely upgrade to Leopard when it goes live without worrying that Parallels will work."

Of course, for Windows PC owners to be able to experience Mac OS X, Apple would have to cough the code. And that's not going to happen. So for now, the only way to have your cake and eat it is to buy a Mac.