I've been using compact fluorescents (CFLs) for years. Wouldn't use anything else. Better light for 20% of the juice.

Incandescent bulbs are really space heaters with a little light as a byproduct.

The CFLs available now have a nice colour light, start instantly, and they'll start up in very cold temperatures (below -20 C).

The only place I don't use a CFL is in my cold room (cold storage for potatoes, squash, and beer). The light is on for maybe 20 seconds at a time. CFLs don't like to be cycled on and off for very short periods; it reduces their lifespan.

CFLs, like other fluorescents, have a tiny dab of mercury in them. It's important to recycle them properly.