Any question answered...

Yeah I figured that'd be the answer. We do it with outsourced Flash at the moment and it works ok. I'm not sure we have the resources to bring it all in-house. Ideally we'd supply an Illustrator file of the floor plan and it would get turned into something we could highlight individual areas on by passing it codes. If Android supported svg we could probably do it ourselves, converting the illustrator files and coding 'em up, ala..

http://raphaeljs.com/australia.html

We're investigating Raphael too, but as you say Android makes svg a problematic solution. Canvas is probably the answer, but as we have to support IE6 too, plain old Divs are providing the most promising solution