Legally, i.e. according to the TOS, you need Snow Leopard. You can install Lion on it's own http://www.macworld.com/article/1161087/install_lion_over_leopard.h

Legally, i.e. according to the TOS, you need Snow Leopard. You can install Lion on it's own http://www.macworld.com/article/1161087/install_lion_over_leopard.html http://www.macworld.com/article/1161087/install_lion_over_le... But it's a bit silly.