Google Desktop Search: Security Threat?

Looks like Google's new desktop search can be a gateway to literally all of a hard-disk's contents:

Google Desktop Search might just be too good. Using the new software, I was able to bypass user names and passwords that secure Web-based e-mail programs and view personal messages sent and received on public
PCs.

Using Google's new software on a shared computer at the Google booth at the Digital Life trade show floor I was able to easily search for, find, and read private Yahoo e-mail sent on the computer by previous users earlier in the day.

Marissa Mayer, Google's director of consumer Web products, told me she wasn't surprised. "This is not a bug, rather a feature," she says. Google always intended people to be able to index and search Web-based e-mail viewed and composed on PC, she says. Google Desktop Search is not intended to be used on computers that are shared with more than one person, she says.

Seeing as some have been raving about this, I'd like to try it... seems like there's not a Mac OS X release (and apparently, they don't tell you this until you start to download an .exe file).