By definition and, communal transport meets only the most common needs. One might lower their aspirations, but it would be like telecom reverting to the party-line phone at the general store.
I take issue with this comment on a number of levels, but today I read an article in the NYT that suggests that "common needs" might be just about all we need. The article is about a study published in Nature that analyzed the movement pattern of 100,000 people in an unnamed European country via cell phone records. The Times write-up didn't have any quantitative specifics, and the study itself is gated, but the researchers concluded that "[i]ndividuals display significant regularity, because they return to a few highly frequented locations, such as home or work." It makes you wonder how necessary the on-demand flexibility of the road/car system really is.
Edit: Reader DS points to this link for an ungated version of the article.