If you switching to Linux, and still need to collaborate with people using Windows and Mac, you should consider using Kerika (www.kerika.com). It is a cross-platform collaboration application that gives you far greater privacy than Google ever will, and also offers a much cooler way of sharing projects, particularly if you are a creative or visual-oriented person.

There's a 2-minute demo at http://www.kerika.com/demo_intro.html that you will find interesting.