Please let's not make it any easier to do this, it's already bad enough as it is. Anyway it's sort of a moot point since the sets of people who take P.T. and those who drive are pretty much disjoint.

I agree, it's annoying. But in Philadelphia, SEPTA has introduced the "quiet ride" program on regional rail lines. The first car of every peak-hour train is the "quiet car": no talking, including cell phones. It's been popular. Not sure how many cities have done it.

A million times THIS! I am a PT user and am already irritated by the conversations I have to overhear.

The ONLY way to manage this inane problem on PT, if it must be allowed, is to enforce "quiet cars", as Amtrak has done on the Eastern Seaboard...of course, then everyone's fighting for a spot in the QC, but at least I don't have to listen to those in the Loud Car (?is that what we call it by default?)!