Two things to remember re this.
1. The vast majority of compact fluorescents have like a 0.5 power factor, so multiply the watts by 2 to get VA. (Not that this matters for heat dissipation.)
2. If it is a recess can, you can't hurt the fixture any by overlamping, but the CF lamp may burn out prematurely. Incandescent lamps give out much of their heat as IR, but the heat from CFs is mostly conductive. The electronics in some CFs can't handle being bottled up in a recess can. And I don't know if there are any that can handle being enclosed in a shower trim.
LEDs are probably going to be the light of the future.
Maybe. The super-phenomenal efficiency that has been advertised for LEDs is based on comparing the output of 1-6 LEDs to very inefficient small incandescent lamps. As the lumens output increases, the efficiency advantage of LEDs decreases. It is practically impossible to beat LEDs for a task flashlight or nightlight, but scale it up to 900 lumens, and they are actually not much more efficient than an incandescent, and much more expensive. CF lamps are the most efficient for most applications.
My sister-in-law had a problem with her hair dryer tripping the breaker. Her condo was built about 1973. There was a 6-lamp fixture over the sink on the same 15A circuit. Since I had driven my car over there instead of my service truck, I just went to IKEA and bought 6 CF lamps for her. Problem solved.
And yes, I wholeheartedly endorse using CF lamps to sidestep the overlamping issue. I have mainly fluorescent in my own home, with a handful of halogens for task lighting.