Do you have a rough overview of how the requirements differ across the similar edge programs linked above? If there's one thing Apple does better, it's providing a clean straight forward page with all the relevant info and little fluff.
The main requirement is how much traffic you need to be doing with the peer before they give you a rack - Apple states 25Gbps; more mature programs like Netflix are 5Gbps. Sometimes that's negotiable and they'll hand them out for even smaller traffic amounts (I've heard less than 1Gbps for some of those listed, though won't mention which ones). Like most things in this area of networking, there's a lot of variability and personal contacts involved.
Everyone also meets up twice a year at NANOG.