Im not sure if there are any differnces or if there is a server. They might just both check with nitnendo to see if your on each others list or whatever then match you up thats why it says something about connection quality before the match. I have played against 1 person from Puerto Rico and im in the USA and i only had 2-3 stars it flucuated. And I guess it dropped to 2 stars because sometimes I could play normal others I would be jerky and laggy. Besides North American being NTSC the others are probaly Pal that might be the other differnce. Not sure tho its a good question.