Are you getting any script errors on the page?
Did you get a google maps api key and enter it in Site Settings API Keys tab?
Is it possible one of the html contents on the page has malformed markup like missing closing tags or extra ones? This could possibly throw off the map.
Are you sure you don't have the map view roles set to something too restrictive?
Are you sure you do not have Hide From Anonymous or Hide From Authenticated checked in the settings of the map?
Are you using my pre-compiled deployment package or a package you created yourself from source code?
Hope it helps,
Joe