I test all of my address strings to make sure they render properly in Google Maps but somehow they're getting messed up so that the embedded Google Map doesn't show the correct location.
To demonstrate, enter "Olympic Training Center, Chula Vista, CA 91915" in Google Maps and see what you get. Then try it as the address in an AI1EC event and see what you get. It's worse if you don't include the zip code.
It looks like "Olympic Training Center" is being stripped out and only the city, state and zip code are being used to determine the address because I get the same results as the embedded calendar when I enter only that information in Google Maps. The correct location is shown when clicking on the "View Full-Size Map" link in the lower right corner of the map, though.
And to speed things up, yes, I've already tried using Twenty Eleven, disabled address autocompletion, and disabled all other plugins.
Again, here's an example of the problem. You can see that the Olympic Training Center is actually further over to the right, closer to the lake. BTW, this is a test site so don't expect perfection if you go looking around. ;^)
And in case anyone notices, yes, I hacked the code so that the map shows up as the hybrid view instead of the roadmap view. It's a one line edit, but it has to be done every time the plugin is updated.