First off, it's just a short list of partners ...
Second, it's possible that AMD are looking towards Global Foundries to manufacture their future graphics chips.
Third, I doubt that either Samsung or Global Foundries are developing a 20nm node so they'll probably have to look at TSMC for the time being until the pair can ramp up their 14nm process node for mass production. They just skipped 20nm altogether and it will be short lived on TSMC's part too.
1-Yes, it's a list of their 16nm FinFET process partners, but it's "curious" to see Nvidia on that list but not AMD.
2-Nothing else to say.
3-Samsung already manufactures nand/other chips on their own facilities using a 20nm process, they don't need to develop it. That's why I said GloFo could use their experience with that node. And AMD is looking forward that 20nm process for the XboxOne and PS4 APUs as noted by a beyond3D posts picked by Eurogamer.
Please excuse my bad English.
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