For those of you who've already gotten Beta Preview or Developer Preview access to Mac OS X 10.10 Yosemite, I highly recommend installing it on a separate partition on your hard drive. There have been many reported bugs and even blank gray screens that prevent access to the system, so if you install over your current OS, you're risking having to boot into recovery or reinstall from the ground up. Installing the Yosemite beta on a separate partition means your 10.9 Mavericks partition will be ...
