I am planning to purchase a new hard drive for my mbp, and possibly upgrade to lion at the same time. I only recently found out that my university software isn't compatible with lion, and the licence is only for the 10.6 version. So in short I would have to purchase lion, an 8gb usb (for clean install) and the updated software for a total of approximately $150 (AUD). Can anyone justify this amount of money, for an os upgrade? I remember when older apple software cost this much, but is lion that much of an improvement over snow leopard?