Related questions: What is in the closet? Do you need good CRI? What are you gong to be doing in there?

My bias would be a linear fluorescent with a program-start ballast, high CRI lamps, and occupancy sensor (lowest lifetime cost), incandescent with occupancy sensor (best CRI) or LED (most costly upfront and long ROI).

One long wall of the closet will have a built-in the whole length for hanging clothes and drawers. The other long wall will have shallow shelves for shoes, purses and the like.

An occupancy sensor is a given - it's required by code here.

Prefer something other than fluorescent.

How about the following
http://www.luminii.com/kendo-closet-rod.html

A light in the rod seems pretty cool until I try to visualize how one would see stuff on the shelf (pictured) above or the shoes that many people keep on the floor. Both will be in the shadows.

On the other hand, the rod will evenly illuminate the tops of the hanging clothing evenly, even the side towards the wall that you don't really need to see. You can have the coolest mood lighting in the neighborhood in your closet since they can be dimmed.

This might impress some guests if you put it in a coat closet near your entry door. You'll get better quality light with a high CRi linear fluorescent over the door in that application. I am guessing for less than 1/10 the lifetime cost.

In my 6x8 closet I went with a 4', four-tube fluorescent, ceiling mounted. Same in my 5x9 pantry, and same in my 7x8 laundry room. I am pleased with the amount and quality of light. I used cheap 2 tube 2' fluorescent in 3 smaller closets, mounted inside over the door -- they do the job, but aren't great lights.

I'm under the previous Title 24, which doesn't require vacancy switches unless the lighting is low efficacy, or you are attempting to get more allowance for kitchen incandescent by using vacancy switches elsewhere (utility rooms, garage, etc).

I cannot recall about the closets, but for bathrooms T24 requires vacancy switches, not occupancy. i.e., the light must be manually turned on.

You could also wall mount the tube fluorescent - that way you don't have to look at it and it sheds light into the closet towards the clothing...we did that with your boys' closets...the light hangs above the door on the wall...no ugly light to look at...
Pam