So, both of your responses to the statement that they don't really do anything with Greyhawk and set everything in FR is that the module they're only just now reprinting was originally only minimally located in Greyhawk and, at best, remains equally minimally Greyhawk? Wow, WotC's really jumping into the deep end with both feet here!
Exactly how many campaign settings have you read that have detailed notes about the culture, population, demographics, imports/exports, geographic features, rulers, alignment, history, deities, locations, etc. of a sea itself? Not the cities that surround it. The sea itself. In my experience there's usually a blurb that says if it's fresh or salt water, what lives in the sea, and then merely describes it as a path for commerce and transportation. If we were to take our map of Toril and pluck out "Inner Sea" and replace it with "Nyr Dyv", what does that actually change? Now what happens when you pluck out Waterdeep and replace it with Greyhawk, populace and all?