I installed Windows 7 64bit using Bootcamp. Then I tried the ZGE-beta and was pleased to find everything working ok except the weird problem that RenderTargets with resolution above 256x256 became very dark. I downloaded the latest ATI-drivers, ran the Mobility Modder-tool to make the drivers recognized, installed and rebooted. Now GPU Caps Viewer reports GLSL 1.5 and GL 3.2 support, and everything is working great including RenderTargets of any size without slowdown! So apparently ATI has much better GL-compatibility on newer cards which is very good news.
I've never owned a Mac before and I must say that the iMac is a very nice piece of hardware. Looks great, extremely easy to install, and also occupies a very small footprint on my desk. I haven't used OSX on it yet but it will be useful later when debugging ZGE OSX-driver.
So, all in all, a good Christmas present to myself

Next, I will install Delphi 2010 and see if I can move ZGE to it without too much trouble.