1- It's generally a good idea to wait for awhile while the unfinished floor gains more acclimation.

2- About 1/16" depending on the actual condition of the installed floor. Overwood/underwood, subloor flatness can play a role in how much is removed as well.

3- They should run the edger right up to the base, but not everyone is perfect. It depends largely on the skills of the finisher.

4- Yes it will come out

I was told by a wood worker friend that I should put a coat of urethane on the floor where all kitchen cabinets will be installed... to seal it. Since, afterward, the finishing will only be where accessible... is this worth the time and trouble to do? I am thinking it would only help if it got wet... and I would hope that no moisture would be escaping from anywhere... my DW uses condensation drying, not heat/steam... the DW and fridge areas will be fully finished anyway. Any problem with unfinished flooring under the rest of the cabinets?

jscozz,

The dishwasher will be a naturally moist area so it is a good idea to make sure the wood is sealed with a polyurethane sealant in order to prevent moisture from seeping into the wood.

As wood gets wet, it swells. If there is a water leak under the sink or dishwasher, unfinished wood will get wet and swell. It could swell so much as to buckle the floor out into the visible area, crack the cabinets and even push out the wall studs.

I'd also use a good silicone sealant and seal the gap between the wall and wood floor behind the cabinets, just to make sure water doesn't seep in there and cause black mold inside the wall.