Was reading the AppleInsider review of Time machine the other day, and they mention something interesting. They say that in order to make "hard-links" work that Apple had to make changes to the HFS+ file system. To quote the article: "To solve both problems, Time Machine does something new and different that actually required Apple to make changes to the underlying Mac file system, HFS+." If they are making changes to the file system, isn't that going to require re-formatting our HDs with the updated version of HFS+? Which would make upgrading not really an option. Or do you think that the installer will automatically update the file system without formatting if you choose the upgrade option? Im going to do a fresh install anyway, but Im just wondering, since nobody has mentioned it before?