Isn't it in the code in the cartridges though...?
Easy enough to update it every/any time you connect to WiFi in the same way AC:WW works. Also, it could be a possibility that trading directly from an English game to a Japanese game will download that data with it - or download a full list ala the Berry Patch corrections from communicating R/S to later games.
There's a pretty wide spectrum of options there to update the list as time goes by anyway.
Since this is the case, there's absolutely no reason not to believe that NoA really was working with NoJ at the same time. o_o
"How DO they make it green?" o_o;
I can think of two reasons to believe that (other than the unreliability of the source):
1) The games still aren't coming out until next year. If NoA had been working on it back when that was claimed then what is the point in waiting on a fnished product?
2) NoE is responsible for a number of the languages there and will be releasing the games even later.
Maybe there was input, as there must be some relationship between the branches, but I don't see it as conclusive proof for full work happening side by side.
I bet GF called/mailed NOA ans NOE and asked for the pokdex entries for the few pokemon they´ve chosen.
Magikarp´s german entry is an old one after all.
It´s not difficult at all and I doubt we can calculate a release date from this info.
The Entries seem to be the ones we had in R/S.