To answer your question directly, it has been my experience/ belief, both with commercial microbrews and homebrews, that 60*F is a perfectly acceptable temperature for aging long lasting ales. An IPA, barley wine, or Belgian strong ale will only show its true beauty after patient aging.
Even when making a lager, I think one should carb at room temp. Once carbed, I think ales can hang out at cellar temps (58-60*F), but I always store lagers in a fridge. Also, any beer that I would ferment at room temp then cold condition after carbonating (kolsch or california common, for example), I'll leave in the fridge until I drink it.
Just my two cents