This image is a draft of my idea, I think that is best put the map in the header as a theme option, down of mozilla tab is a good place and move the logo to left, before the name of the community.
Working in the site of Mozilla Québec I do a nice map and David Bpswell say me:
I also really like the sidebar of regional maps on your site. It would be cool to package that up so other local sites could use it too.
And Soumya Deb say me:
Thanks for coming forward with the idea, it’s really cool! I think the best approach will be to make an WP plugin…