I'm working on a interactive map for the 2011 FOSS4G website to show all of the FOSS4G venues and local amenities. I'm showing the local amenities with a tile overlay and listening for click events on the map to send to a back-end select service. I'm getting slightly offset values for latitude when clicking the map in Chrome and Safari. When I use Firefox the map selection (add marker through GeoJSON layer) works fine.

You can view the map here (http://2011.foss4g.org/content/foss4g-map). In Chrome/Safari, if you click just above the various icons for pubs, cafes, restaurants etc the selection works fine but if you click in the center of the icon it does not work.

The really crazy thing is that this isn't an issue where I've been developing this application (http://foss4g.geojason.info). The code base is exactly the same, it's just that the (soon to be) production map over on the FOSS4G website is using Drupal (div > div > div > div > div) for a CMS and my development site is just very simple CSS.

When testing this out note that the FOSS4G logos on the map are markers, not tiles. So they work fine when clicked.

Do you think this could be related to #206 or #215?