The NYT has an article here - http://www.nytimes.com/interactive/2010/04/25/nyregion/spokes.html - about 5 of the obvious "tribes" on the roads in New York.
In Calgary, the Bespoked Rider is definitely the rarest variety of cyclist - but growing, and for our purposes, we would also need to add the following "tribe" -
Bike - beaten down MTB with clip on fenders
Clothing - MEC jacket and pants, backpack, and multiple flashy lights
Manners - Madly dings bell as they try to pass as many people as possible during their commute. Rarely rides slow enough to appreciate surroundings. Is considered a menace by many other pathway users - including other cyclists.
Maybe one more "tribe" -
Bike - beaten down MTB, usually a mass-market brand
Clothing - whatever they have found during scavenging or functional winterwear you might find at Marks Work Warehouse
Manners - usually rides slowly, frequently with large garbage bags that triple their effective width, can be found on both bike paths and walking paths, and can be found on the sidewalk downtown. Generally mind their own business.
Are there any other Calgary-specific "tribes" you can think of?