It's an attractive fantasy -- instead of diving a Hummer, living in a McMansion and shopping at the Gap, I can drive a Prius, live in an EcoMansion and shop at Gaiam -- but it's still playing make-believe, because the systems that support and enable those choices are themselves unsustainable. Highways are destructive, even when full of hybrids; sprawl is unsustainable, even when the individual houses are green; we don't even know what sustainable clothing would look like, much less how to make conventional retail green.
No, if we're going to avert ecological destruction, we need to to not only do things differently, we need to do different things. We need to work to build dense, walkable neighborhoods composed of green buildings served by bike infrastructure and transit and green infrastructure, suffused with good design choices and smart technologies that let us live in a different set of relationships with our stuff, the materials we use and the energy that powers our lives.