I personally don't see a VaporMg based phone product being produced. There are a couple reasons.
1. VaporMg does not allow for antenna signals to penetrate the shell of the device. As such, the antennas on a Surface are at the top of the device in the plastic molded section. At release, the reason MS gave for not including NFC was the specifically their choice in using VaporMg. Phones locate antennas all around the device, not just the top.
2. VaporMg, or at least it's use on the Surface and Surface 2 make it too heavy to really hold and use like a "tablet." No matter if you have a Surface XX or Surface Pro XX it's too heavy to do anything with other than use it like a laptop.
I have my Lumia 1020, my Dell Venue 8 Pro, my Surface 2 and my Desktop Media Center PC. If ATT releases a phablet with wireless charging, I will replace both my Lumia and Dell tablet with that one device. Otherwise, the Surface is too heavy to hold for reading or consuming data.
I would expect that future Surface branded products may not use VaporMg going forward or will use it more sparingly to bring the weight of the device down to a more competitive weight.
But that's all my opinion and we all have opinions....
