I own the 1st generation MacBook, purchased in June of 2006, and I'm using Tiger OSX 10.4.11. I went and spec out the new nano on apple.com today, and to my surprise OSX 10.5.8 a.k.a Leopard is required. I don't use my computer for much other than surfing the web and watching TV shows on Hulu etc. Listening to iTunes and using the web for news and tv constitute about 99% of my computer usage at home, so there is no need to upgrade IMHO. My MacBook works well as is, granted the battery only last a few minutes now, but I never unplugged. It turns out I can't purchase any of the current iPods except for the Classic unless I upgrade which cost $169 for the OSX Box Set. To further insult my "old" MacBook, I can't buy an iPad nor an iPhone, current model of course. An one more thing, I can't use iTunes 10 because it requires 10.5 or later. I am not alone here, because I believe there are a significant albeit minority of us still using OSX Tiger. I take pride in keeping my MacBook running, thank you very much. I don't want to "recycle" my MacBook nor sell it, because it works fine! GM (General Motors) invented plan obsolescence, but Apple took this idea to new heights! Shame on you Apple!!