I ride bikes, I used to race bikes, They are the greatest local transportation. They can get you out 10 miles or even more, they're great exercise, reduce air pollution. They can help us solve our diabetes crisis and air pollution. When there are paths for bicycles they are used from what I have seen. Bicycle commuting makes up less than one percent of commuting so it really is trivial, but when there are trails people really do ride to get places on them so we need to build more. And people must want these because houses are more expensive in areas with bicycle trails, so there aren't enough. I find it ironic that when there is a bicycle trail the house prices go up so much because then only wealthier people can afford to live close enough to a trail to save money riding a bicycle instead of driving. Actually neighborhoods with trails for bicycling or walking can be so much more expensive than other neighborhoods it negates the cost savings so we really need to make more so these neighborhoods become affordable.
Look whats going on in Salt Lake City where I used to live: https://www.google.com/search?q=salt+lake+city+air+pollution&hl=en&client=firefox-a&hs=XBL&tbo=u&rls=org.mozilla:en-US:official&tbm=isch&source=univ&sa=X&ei=kCgNUY_6DMbX0QGCuYCoAg&ved=0CEEQsAQ&biw=1525&bih=690
Or worse in Beijing: https://www.google.com/search?q=beijing+air+pollution&hl=en&client=firefox-a&hs=zCL&tbo=u&rls=org.mozilla:en-US:official&tbm=isch&source=univ&sa=X&ei=6igNUePqAsu30gGly4DwCA&ved=0CEwQsAQ&biw=1525&bih=690
This bicycle even gets power from the brakes to use for going up a hill: http://senseable.mit.edu/copenhagenwheel/. Since it's not the Tour de France we are allowed performance enhancing technology.