Isn't Ottawa's system pretty much a Bus Rapid Transit scheme. Dedicated Bus right of ways combined with fixed stations (bus stops on only a few stations, always stops at them and does not allow for people to push for stops), fixed routes, and a frequent time table.
They have one in Boston called the Silver Line, where some of the Buses run through converted streetcar tunnels. It has its benefits but I reckon it should just be turned into Light Rail.
The O-Train is a light rail system isn't it? it complements the BRT systems.