This is not terribly high priority, but...
Google's map API lets you put an overlay over a map to create, e.g. a map with driving directions. But for IE, you need to be able to add a VML namespace by modifying the html tag along the lines of:
html xmlns="http://www.w3.org/1999/xhtml" xmlns:v="urn:schemas-microsoft-com:vml"
Would need a mechanism to be able to add this to a Caravel html tag.