They last for 5 years under ‘normal’ use on average which is 3-4 hours a day. Like anything, there will be some that last longer and some shorter than the average. I’ve had normal bulbs die in 2 days before and others last over a year. In general though, you’ll get about 2,000 hours out of a normal bulb, and 8000 out of a CFL.
My evidence is anecdotal, but significant, and I have found the claims of CFL life to be greatly exaggerated. Upon further reading, I’ve learned that they only last if you turn them on and leave them on. Ons and offs significantly reduce their lifespan.