@Raptor: Yeah, there would be something really neat about having the third park there, all of them centred around the angles of the compass on the hub. The Imagineers could create a great entrance introduction to it with that long path past the village and bus station.
It might depend on just how many parks/visitors that one hub can handle though? It's sometimes
busy enough with people rushing to just 1 and a half parks...
That's what I think as well... it might get awfully busy having a third gate bordering the esplanade...
Imagine: a day with 50.000 people at DLP, 20.000 at WDS and let's just say another 20.000 at a possible third gate... you've got 90.000 people that have to cross through the esplanade...
Not to mention public transport for all these people! Let's say that half of them came by care - you would have to transport 45.000 guests from a new parking lot to the parks...!!!
(Let's just say that there's a reason why the MK at WDW is the only Disney park with such a setup...)
For now, the area that is earmarked for a possible third theme park are the fields between the entrance / exit road to the existing parking lot and the Boulevard Circulaire that runs around the resort and the urban centre of Val d'Europe. (The partner hotels of Val de France would be situated right next to a new parking lot for this 3rd park, to give you an idea...)