Yesterday I picked up an interesting book, Divorce Your Car! : Ending the Love Affair with the Automobile, so I'm thinking about this right now. Dave, I think the 'Circles' blog posting you made months ago fits very closely to this book. Most of the book goes over various strategies to decrease dependence on cars for getting around. I've tried most of the ideas..
I think a key to having it work would be a return to densely populated urban areas. This book goes over the history of how Americans adopted automobiles, and how there was essentially a propaganda campaign selling us on cars. To make it feasible for Americans to own and drive cars the powers-that-be had to reshape cities to make wider streets etc. It resulted in non-dense suburban areas where it's not very feasible for mass transit to be effective. Mass transit is effective in places where population is densely enough packed that there's enough ridership to pay for enough mass transit that you can expect the bus/train/etc to just be there.
At the same time I love traveling and seeing foreign countries. That's one of the advantages we have today - because travel is ubiquitous it helps us understand the ways other people live. It seems to me the travel that needs to be optimized is the travel we do every day. My daily commute is the most travel I do, so optimizing how I do my daily commute would give the biggest benefit.