I read through the previous thread on Global Food and I don't think the evidence is convincing that this will be the case. In fact, the IGN article seems to suggest that city-based food will still be in, meaning that you need to balance Food production against District building.
I also wouldn't like a global food mechanic, I think that it abstracts the concept of feeding your citizens in such a way that is at odds with the geographically tied district system.
Food transfers (but NOT the Civ 5 trade route food transfers) would be a great mechanic to implement though.