It took one day to get the granite/marble laid, and the contractors came back the next day to set the base"board" and grout everything. We're pleased with how it turned out, and, if it wasn't before, it's very clear now that this bathroom will indeed be quite different from anything else we've done so far (even though the toilet will be the same and the sink will be very similar to the ones we put in the hall bath).
Now we can hardly wait to start installing all the actual bathroom stuff, most of which has been waiting in boxes in the bedroom for awhile. The toilet will go in soon, but I want to wait until the tub is in place before installing the sink; carrying that tub in there and getting it positioned right (without chipping or scratching the floor) will be quite a chore, and having the sink in the way would make it all the worse. The tub should be finished and returned to us by the end of next week, so if all goes smoothly I expect to have everything installed by next weekend. Also, we ordered a couple square feet of black and white marble mosaic to go right above the sink as a backsplash. Hopefully that will be in by next weekend as well.
I believe the end is in sight.