It's true that "yuppies" are much less likely to ride buses. The possibly apocryphal quote (the internet seems to make all quotes possibly apocryphal) from Margaret Thatcher is "A man who, beyond the age of 26, finds himself on a bus can count himself as a failure." There are good and bad reasons for this.
Obviously there is the Thatcheresque class association. Poor people ride buses! Paint it green and tart it up to look like a fake trolley and such people will ride them because they associate those with tourism.
But there are good reasons people don't like buses, though some of them can be improved upon. Buses are generally slower and less predictable. The rides are bumpier and less pleasant. The routes aren't as fixed, and people are less sure where they go. Get on the wrong train and you can just get off at the next stop and return. It's less clear what to do if you go wrong on a bus.
But you can make a better bus system. With GPS systems you can have real time information at bus stops about when (and what) bus is arriving. The simple step of having good up to date maps and schedules, along with fare information, at bus stations is a big help. Transfers to/from other buses and trains should be free and easy. Express buses which don't stop every block should be on some routes. Giving buses the ability to force a stoplight change improves speed.
Lots of ways to make buses better, some of which require little in the way of capital expenditures.
Still they aren't a substitute for fixed rail. An important element of a transit system is to have it impact land use patterns, to have denser development around transit routes. Since bus routes aren't fixed, they're less likely to lead to land use changes.
After my nightmarish confrontation with Roger Simon, I rode the elitist bus home.
