Most people know that the regions shown in the games and anime are based loosely off of Japan. Starting with Kanto, where I think Tokyo is IRL; then Johto, to the west; and Hoenn, which is a large island in the south which has a lot of smaller islands around it. The Sevii Islands of FR/LG are an archelago I assume to be pretty close to Kanto, since the Seagallop ferry can still reach it. In the anime, there is another archipelago, the Orange Islands, which are south of Kanto. Orre, I don't think has been specifically located in reference to any other known region.
That is all that is know. If anyone wants to fill in any gaps I missed, feel free, but what I put this here for was I noticed something while playing FR, and that is references to real life locations. Lt. Surge is the "Lightning American", that would have to mean he is from the US. The cooking staff seems to speak in a mix of French and English, and the rival even says "Bonjour." (reference to Europe, specifically France? o.o) The location Mew is found is Guyana, South America. Does this mean that the Pokemon world is much bigger than we think it is, and doesn't entirely consist of these odd-named regions, which to my knowledge, don't really exist except for Kanto? If this is so, then the possibilities for the Pokemon world are virtually endless.