Following the instructions in the Gentoo wiki, I managed to install and run Google Earth in Linux, but only after trying my luck with three different Wine versions (0.9.4 did it for me, finally).
After going through all these troubles, I must confess that all the effort seems to have been in vain (sort of): though I am able to zoom in and out and twirl the globe with my mouse, the menu items and the navigation buttons appear only when I hover the mouse over them. I also haven't figured out how to input coordinates and zoom there directly, if that is at all possible.
Put me down for Less Than Impressed.