I would say The Active Contributors--The people contribute to open source projects mailing lists etc. These people help promote certain "styles" of programming over others. They contribute to make the things that work even better. These things they create are then consumed by other members of the community.
Also, IMHO there are no superstar programmers who can influence developers. All the good devs i know are too arrogant to take any suggestion based only on who suggested it.
I'm not sure that's a useful comparison. I would argue that plumbers and electricians have a more clearly defined problem space with a large body of existing solutions and conventions. Programming as a trade, or craft however is considerably less mature and what may look to you like developers choosing tools based on fashion is probably more a reflection of how far we are from settling on a the _right_ way to build software.