Lots of riders in my area, but when someone finds out that I bike commute, the first question is always "How far do you ride?" too.

I've never had anybody ask me if a particular type of bike is needed to commute.

If someone says "I can't do that (bike commute)", it's always because he/she feels it's too far - eg. Laurel MD to DC (20 miles). I ride 13 miles each way myself, which I guess is nothing to veteran century riders and the like, but there doesn't seem to be that many people that would commute even 10 miles.

It's never because "I can't find a proper Dutch bike".

With the Metro's impending SafeTrack program, which involves lots of single-tracking and shutdowns of segments of Metro lines, there does seem to be more people looking into some kind of mixed modal solution. I have a coworker who lives near Baltimore that is considering doing just that, using a bike and the MARC train.