Depends on the difficulty level, map type and style of play.
As a builder at Regent and above, the ages will go pretty quickly if civs have contact with one another. The AI trading bonus will speed tech along. As a warmonger, things slow down. Seriously. If you break AI civs, you hurt their collective research power, and thus slow the technological progress.
Having said all that:
Chieftain: ages (all) move too slowly
Warlord: ages (all) move a bit too slowly
Regent: ages (all) are pretty much fine
Monarch: ages (ancient/medieval) a bit too quick, others ok
Emperor: not much experience... but is obviously quicker than Monarch...
Diety:
-Arrian