I found this purely out of luck. Apparently, Rolex just got a new patent issued on its big date mechanism today. I haven't read through it, but if you scroll all the way to the bottom, you can see the claim.
Anyway, I'm sure watch companies file tons of patents every year and this doesn't mean they are going to make a big date watch. However, it means they have the technology ready.
Anyway, if you want to see it, you'll have to download the following PDF.
Enjoy!!!!