I am personally wanting it to not have a set geographic area. I want the game to grow and expand as a player makes progress in the game. Every player would start are in a set area, such as Cali. After they have helped achieve all that can be done in that area it would then open up quests for other areas. They could pick to goto any number of other locations to help out. They could pick to help out in Texas, New York, Florida, or any other state. Each players progress is seperately from other players but also connected in the over all purpose of the area.
Example: 10 players goto Washington and 5 players goto Texas. The Washington area would improve and gain ground far faster than the Texas area. Now this would only be possible if you put a limit on what each player could see. For instance, if player A went threw everything in Texas he would be able to see everything. Player B just arrived in Texas so he would still see the burned out ruins that it was before the brotherhood was able to get in there.....
Now due take into account that my thoughts on Texas being a fallout playground as bad ... but come, on we all know Texas would become the true superpower in the world if the bombs did fall
BTW, sorry i been gone for some long, haven`t had the internet.
Just remember, an amature built the ark ...... professionals built the titanic ....