You can install on a clean hard drive and you can put it on a USB thumb drive. Check Macworld.com for all the details. It is more that a service pack. The 200+ new features really takes the OS to the next level in computing.

So while I can have the future at home, I have to use Windows XP, a true 10+ year old OS at work. Next year we might get Windows 7 so I'll only be 5 years behind!