Where most of the game software development are located?

Game developer map.

LA (and area around it) would probably be among top 3, if not top 1.

It's global now. It use to be concentrated in the LA area and few select overseas locations, but it's expanded to all around the world. From the map you can see Europe has a large concentration and the American east/west coast also have studios. Though the largest studios are probably in California, Britain, Canada and Germany in that order. Cities wise probably LA, Montreal, London..

-ddn

I'd say that there's probably more in Vancouver than Montreal (although Montreal is still growing).

I don't know what the situation is in Europe these days, but I'd say top 3 regions in North America are:
1) LA (well...SoCal anyways)
2) Pacific Northwest (Seattle/Redmond/etc.) and Vancouver
3) Montreal

There are lots of companies in those areas including the big ones.

Thanks a lot for figuring it out.

LA on the top is interesting, cause it's not hi-tech industry area.
Is it because of relation to entertaiment?

Other than some of the more standard locations (California), another spot in the US that's really growing with game dev is Texas (obvious when you look at that awesome map). I know of several game companies down there, some of which a few of my friends work for.

Lots of companies seem to be migrating away from massive cities and more into scenic suburbs, places like Washington (Bungie, and (previously) Cyan). Another spot thats gaining studios is North Carolina where we've got Epic Games and the new Insomniac studio. These studios are near large cities but not near the size of something like LA or NY.

For awhile there was rumor Madison, WI was growing as a game dev hub but I've come to doubt that considering the relatively mediocre performance of the Raven software games and Human Head games kind of changing to more of a board game company.