I like the watch a lot, and at 40mm it's a versatile case size. My office mate, and good friend, has an anniversary edition with green crystal and it's a nice-looking, cleanly designed, proportional watch with a fantastic element of whimsy (lightning bolt seconds hand). Even folks at the office who know nothing about watches seem quite attracted to it. I think the black dial Milgauss is probably the most versatile, but I myself like the lighter dial.
Would the watch be more attractive with a 42mm case? Maybe...and like you, I wonder if Rolex will move it up a size, but honestly it's such a handsome timepiece as it stands that I don't think a change is necessary. The current pricing for this model is quite good IMO.
Please let us know if you end up with one! 
Cheers,
Daos