DH's current setup is one 36" vanity and a two bulb fixture. The new setup will also be a 36" vanity with a three bulb fixture. The mirror in the remodel will cover the expanse of the vanity. I questioned (here) if 3 bulbs would be an overkill. Everyone said to go with the three bulbs. So I'm sticking with my original three bulb plan. Besides, the overall decor will be darker so we'll need the extra light. His bathroom is 8x5.

coody, if you have to check up on every single item your contractor is doing are you sure you hired the correct guy?

I have a 21" three-light fixture over a 24" mirror over a 36" vanity. Looks balanced and provides plenty of light.

The one we're going to use is 24" wide centered over a 36" vanity. That leaves 6" on each side of the fixture to the edge of the mirror.

I wanted to add that my mirror is frameless. If you frame it, you might go bigger so you don't lose too much of your view to frame.

Make a scale drawing of your wall set up on graph paper. That way you get to see if the lights overpower the size of the mirror or not. Select something you like to look at. More light is better, IMHO. It is always possible to downsize the wattage and bulb types, but you cannot upsize in any given fixture.

In my pre-remodeled bathroom I had 12 globe lights over a 7' vanity.

In my post-remodeled bathroom I have 5 on top and sconces on either side, plus recessed ceiling lights. Choosing the type of light bulbs is a whole nother deal. Good luck. What you don't want is shadows, whether you are shaving or applying makeup.

-Babka

I have a 5-light fixture over my 57" vanity with one sink. I use 5 40-watt globe (hollywood/boob) lights and they provide enough light for the entire 5 x 10 bathroom.