No one is forcing anyone to upgrade their Mac OS system software. There is no gun held to your head. You seem to be sadly and grossly misinformed about almost everything. Either that or you have some pathological compelling need to validate arguments against something you chose not to invest in. Probably a little of both. While every up rev from anyone obsoletes software versions requiring they be updated, this upgrade does not make any hardware obsolete. What current (non-Snow) Leopard runs on is any Intel-based Mac, and that is also what Snow Leopard runs on. Leopard itself will not run on PowerPC Macs, but they have not been sold for years. And they are also not obsolete. My PowerBook is nearing 7 years old and still running strong on Panther. The improvements in Leopard, or even Snow Leopard over Panther are just not that compelling anyway. If there were a lot to fix in Panther, maybe so, but there never was, as it was pretty sound already. Comparing the SL release to Vista is ludicrous. As with every other Mac release, Leopard broke very little, while true to form at Microsoft, Vista broke nearly everything. Mac's OS releases have been astounding technical successes while Microsoft's have struggled to the point where vendors themselves rejected Vista, mutinied, and moved back to XP, the only relatively-stable consumer OS Microsoft has ever had. Mac's popularity is not based on a desire for something different, unless you mean different than Windows, typically because it is so much more reliable than Windows. It is also not a function of advertising, although if one were to make a decision on what to buy strictly on advertising, Apple's commercials would be a compelling reason to buy Mac while Microsoft's commercials would also a compelling reason not to buy Windows. Mac's popularity is based on how terrific and reliable the Mac OS actually is. There is nothing really comparable to it on any level. One of the remarkable things about Snow Leopard is that it actually gives back 7-20 GB of HDD space, which should tell you something about the design ethic at Apple. I think that I can safely predict that Windows 7 will give nothing back in that regard, and just be another continuation of software bloat. But who knows, a broken clock is right twice a day, so they might even get it right for once.