As reported in Ottawa Rewind it looks like the new owners of the building are looking into restoring this iconic sign. An Ottawa landmark! That would be great! I do remember it lit and spinning but I have to think really hard.
I always thought the building was mid-century modern but I read that at the time that specific style was called Googie style, a subsivision of futurist architecture which derives its style from cars, jets, spaceship, and the atomic age – Oh I feel another architecture post coming on.