I don't know how the D7200 can be way better in low light with the same sensor. It might focus better, but final image should be almost identical to D7100.
Also, I thought all Nikon DSLRs had built in time lapse for quite awhile now. It looks like a nice rev, but if I had a D7100 I don't know if it would be worth it to jump if it doesn't fit the same housing. To me, the best change is increasing the buffer size.
BTW, I'm not contesting what the original poster wrote, I'm questioning the Nikon ad blurb.