Past versions of Mac OS 10.x have been pretty much applicable to all of Apple's past computers. Typically, they would introduce revolutionary features or applications, along with enhancing the overall user experience, which could be realized by even older Macs. However, I have to say that I'm disappointed that two core features built into Snow Leopard, will only be realized by computers that are less than one year old when Snow Leopard is launched. Of course, this wouldn't be as big of an issue if Snow Leopard were such a large improvement over Leopard, but it's list of improvements is fairly limited - therefore one would expect these improvements to be available to all. These two features are the multi-gesture using the trackpad, and the general GPU performance acceleration (OpenCL). One may argue that the new glass trackpad contains hardware that isn't found in older Mac laptops, However, Apple claims that Snow Leopard will enable multi-gesture functionality for computers that previously did not have it, and at one time, were unable to recognize multi-gestures. That said, Apple intentionally disabled multi-gestures on the track pad for "old" (older than one year) Mac laptops in an effort to sell new ones. I could understand if they dropped support for computers 2-3 years or older, but 1 year? That's irresponsible .. The same applies to GPU's. After researching, Windows 7 is going to support many more video cards that are on the market now, even those that are older. Clearly, this is Apple trying to push new computers out the door. The longer Apple stays in business, the more I dislike them as a business ..