Copy-pasting from http://www.gamesas.com/bgsforums/index.php?showtopic=1075725 previously on the http://www.gamesas.com/bgsforums/index.php?showforum=77 board:

Hawaii would be so perfect for the next, post-NV game: an America outside America, to bring something really fresh into the show, not to mention the added elements of an aquatic environment between the islands - maybe there could even be an artificial island, made of metal, predating the War or maybe built later out of the wreckage of hundreds of ships.

While Fallout is mature enough to expand into other areas of the world, as you often see some people suggesting here, the American motifs are what make Fallout what it is, so Hawaii could be the best of both worlds, as it were.

Discuss and expand, if you like. I'll keep updating this original post with any solid/fleshed-out ideas others bring in.

Well, if (according to the Fallout 2 intro) "whole continents sank under the boiling oceans", I would think Hawaii is gone now.

You already have one topic on this, and if you wish to speculate or suggest about things for any future games, we have a thread for it.

http://www.gamesas.com/bgsforums/index.php?showtopic=1067662