With the official release of the Windows 7, Apple has announced that Boot Camp in the Mac OS X Snow Leopard will support the OS by the end of the year. A software update will be released to offer full support of the Windows 7 Home Premium, Professional, and Ultimate editions. Only Intel based Mac ccomputer will be supported and the following models are not supported:

• iMac (17-inch, Early 2006)
• iMac (17-inch, Late 2006)
• iMac (20-inch, Early 2006)
• iMac (20-inch, Late 2006)
• MacBook Pro (15-inch, Early 2006)
• MacBook Pro (17-inch, Late 2006)
• MacBook Pro (15-inch, Late 2006)
• MacBook Pro (17-inch, Early 2006)
• Mac Pro (Mid 2006, Intel Xeon Dual-core 2.66GHz or 3GHz)

Many people actually have been using Windows 7 on their Macs without any problem but it is always a good idea to have a full support with working drivers.

Source: Apple