Personally I'm looking at going back to a gaming machine anyway now that I don't need something portable. Still, I feel it was a silly move using an M370 over a GTX 950M, but that's just my take on it.
I agree completely. The 950m has a lower TDP, 45 Watts vs 50 Watts on the M370X so it would have run a little cooler. It's also faster. Some sites are saying it's 20% faster than the M370X.
I think based on their products with dedicated cards all going AMD for graphics (Mac Pro, iMac, MacBook Pro) that their relationship with NVIDIA is not in a good place. NVIDIA have chips at every price segment and power envelope which are faster than AMD's equivalents. For Apple to not use them makes no logical sense except for some kind of falling out with the company.
Also I suspect it may have something to do with NVIDIA's unwillingness to change products to meet Apples product goals. AMD took the HD 7970 and rebranded it as the D700 for Apple. This is not the W9000 as it doesn't have ECC memory and all the specifications match the HD 7970 exactly.
I think Apple likely had a discussion with NVIDIA around early 2013 about rebranding the GTX Titan or GTX 780 as a Quadro type card, lacking ECC but gaining the professional branding that people would eat up and be shocked at the low price point. Remember the W9000's cost more than the Mac Pro does which is why we got D700's instead based on the consumer HD 7970.
AMD will apparently do whatever it takes to score deals these days because they need to, they are the underdog and I'm sure you all know they are supplying the APU (CPU+GPU in a single chip) to both the XBOX ONE and PS4, they are also the GPU supplier for the Wii U, that chip based on the HD 4000 series from AMD but rebranded as Latte by Nintendo.
I hope Apple will continue to offer dedicated graphics because as good as Intel is getting the dedicated chips aren't simply frozen in time. NVIDIA especially has pushed efficiency so high with Maxwell (their current architecture) that there is little reason to buy anything else. Even the Fury X released by AMD just yesterday fails to match its rival the GTX 980 Ti, yet they are priced the same at $650.