http://news.motorbiker.org/blogs.nsf/dx/using-motorcycles-eases-congestion---scientific-study.htm I haven't dived into the specifics of the study - I think a key criticism could be that it looked at limited number of roads... but at the same time that could be one of it's key advantages - these are the savings found on one stretch of a motorway. Imagine the savings if the savings were replicated throughout the road system! There's also a section on pollution and their figures show that pollution is reduced using PTW's (and they specifically thumb their nose at Myth Busters who said the opposite). We already know this stuff, but the more that studies show carcentric cities benefiting from a modal shift, the better it will be. If you're on a car forum or other forums, spread the word!