Maybe I'm going senile but I thought filenames on the Mac were case sensitive (e.g., "test" is a different file than "TEST") just like under Linux. Working in the terminal today, however, I found to my amazement that this isn't true. I've been a Mac user since 1984 but now I'm really questioning my memory and/or sanity. Is the Mac (Leopard OS) case insensitive or is it not?

I would more personally question your sanity. Why in the world would anybody want case sensitivity in file names??? Is your vocabulary so limited that you can't think of words to name your files?? Anyway, to answer your question, the apple developers are finally coming to their senses and decided to do away with stupid features like case sensitivity. However, the leopard has a touted feature called Time Machine, which is like the Windows System Restore on crack. Never in my life have i seen a proficient way of squandering disk space. If you're looking for a new operating system that's fast and easy to use i'd recommend Windows Vista Ultimate. But if you're a low life geek and you prefer to tinker with computers on your free time instead of being active in your community then, i would recommend Ubuntu Linux. Cheers!