I would presume that the newer products such as "DEX/MERC" and the like get around the non-license issue because they do NOT use the full product name of Dexron III or Mercon. That addresses the label wording and makes it legal to use, yet the product is still recognizable to most people, as it sits on the shelf.
As for the formulations? I would expect they are basically the same as they had been, before the licenses expired. Techinically, since there is no license to be obtained, then there is no current "authority" by GM/Ford to control the formerly-licensed products. Still - I expect that large companines such as Mobil, Valvoline, Pennzoil, Castrol, etc are interested in the balance of marketability, profitability, quality, and image; they are, in fact, always in this light. So I expect that there's been little if any effective change in the forumlations moving from Dexron III/Mercon licensed fluids to "DEX/MERC" non-licensed fluids.
I agree that the DEX VI product is a vastly improved one over III. However, if you use a DEX/Merc unlicensed fluid, you'll just have to stick to the old OCI, that's all; I expect that they will perform more than adequately.