From what I have seen and heard:
key programming
take off protection tape
installing wheel caps/covers
installing radio antennas
setting radio codes
topping up fluid levels
tire alignment
headlight and brake light checks
warning light checks
installing licence plate holders
short road tests
(at most dealers, sales people install the actual licence plates, not mechanics)

Total time spent varies from 0.5 - 1.5 hours depending on mechanic
None of the PDI money goes to the salespeople or sales office.
I don't know what the split is between the dealer and the manufacturer, maybe some of the PDI money goes to the mechanic (I guess no more than $100) but most would be going to the manufacturer, will try to verify in the future.
The dealership's sales department makes peanuts "compared" to the manufacturer.
Which HQ is hiring?

key programming-Well shouldn't one expect the remote key that they paid for as part of the car to work? But sure it can only be done at the dealer so lets accept a mechanic has to do it.
take off protection tape-A wash bay/detailer can probably do the same likely better (because he works with exteriors all day long)
installing wheel caps/covers-If you need a qualified mechanic to do this something is seriously wrong (how come PDI isn't less if you have alloy wheels)
installing radio antennas- what part of mechanic school to do they teach someone to insert 6inch antenna into screw hole and turn 3 times?
setting radio codes-Seriously? You pay part of $500 to have someone tune in local radio stations you may or may not want (or even just push the "autostore" button?
topping up fluid levels-Unscrew washer cap-unscrew cap from washer fluid-pour-screw washer cap on -dispose of fluid container Thank you master mechanic
tire alignment-Understandable because of issues with shipping. Retail (including markup) cost is $69.95
headlight and brake light checks-Yikes this one is expensive since you need 2 highly trained mechanics to perform it one to push the brake pedal and the other to say Hey the brake lights are on
warning light checks -see above
installing licence plate holders- How come I never got a discount? IN Nova Scotia we don't need front plates so I always tell them to leave the front bracket off?
short road tests- I guess this is to see if they notably missed anything they should have found while doing the PDI that the customer might notice when they are still driving close enough to come right back rather than not notice for a week until they have to come to the service dept for warranty?
Seriously JSCC thanks for stepping up to the plate and providing at least some of what dealers so tightly guard.

But if this is true:1. They are hosting service dept profits by using a highly paid mechanical rate to do Joe jobs 2. Are charging extra to simply deliver a fully assembly and operational product as expected.
Programming key fobs, putting on wheel covers and antennas? What is this "some assembly required"?