The 60W limit is based on the heat generated by an incandescent bulb. You can use any size compact fluorescent that fits.

Good. I figured the rating was only about heat generated. Gosh, now I'll be able to see every wrinkle! Thank you.

Two related questions:

Do I remember that you need to leave fluorescents 'on' for a while or they will burn out quickly?

Are they 'dim-able'? These sconces are on a dimmer switch. (I can leave it full on, of course.)

Some CFLs are dimable, most are not. I'd recommend replacing the switch to preclude accidental supplying of partial voltage.
'Flickering' a fluorescent will cause it to burn out faster, as it will an incandescent bulb, but that's due to the number of on/off cycles rather than the amount of time it's left on.

"Some CFLs are dimable, most are not. I'd recommend replacing the switch to preclude accidental supplying of partial voltage."

Even when fully ON a dimmer distorts the voltage to a light.

If the CFL is not rated for dimming it is likely to be damaged from overheating the ballast if a dimmer is supplying the power.

OK, I give up. This actually involves TWO separate switches and TWO sets of sconces (over my sink and DH's sink).

Would I be courting a fire if I put 75W incandescents in these sconces? I just need a leetle bit more light.

"Would I be courting a fire if I put 75W incandescents in these sconces?"

What does the label on them say?