If you ever are considering switching your business over to Macs, let me warn you in advance of a little tidbit I learned today.
Say you have a mission-critical application you're using, and you're using that application on Tiger. Suddenly, Leopard is released. Your mission-critical app doesn't work on Leopard, so you choose not to upgrade to Leopard. Fine.
Here's the kicker... when new machines are released, they will not run Tiger. Apple will not let older OSes run on the newer machines, they won't supply drivers. So if you end up in the situation where you need more machines, but you can't afford to upgrade everyone to Leopard because that mission-critical app doesn't work, you are screwed. The new machines you need to buy won't run your app.
And there you have it. I hadn't realized this until a Mac user mentioned it on a mailing list I'm on.