Raise your hand if you remember when a Mac was a Mac and a Windows machine was a Windows machine, and never the twain shall meet. I sure do.
Change has come.
Our own Christina Warren has written an exhaustive set of instructions for installing Windows 7 on a Mac over at our sister site, Download Squad. Windows 7 is in beta, so don't try and use it for any mission-critical tasks. Meant to be an incremental update to Vista (Snow Vista?), the current iteration of Windows 7 includes changes like a redesigned taskbar, enhanced touch performance and improvements when run atop multi-core processors.
While Intel Macs can run Windows 7 via Boot Camp, Christina points out that virtualization is probably the best bet for most users. She described how to set up an installation with VMWare Fusion 2.0, Parallels 4.0 and VirtualBox 2.1.2 (and the VMware team has posted a guide of their own for Win7 on Fusion).
If you're a Mac user who keeps Windows around for compatibility testing or that one proprietary Windows app you can't do without, and you're just itching to try Windows 7, this is the tutorial for you. If you're wondering what the fuss is about over on the Microsoft side, Engadget's deep dive on Windows 7 is a good place to start.