Using SVG would be the easy way (open up Illustrator, draw some circles and export). As developers we should be pushing ourselves, trying the seemingly impossible and keeping our brains sharp. If developers all used pre-existing and practical solutions as I pointed out earlier, we would all still be making websites that used tables for mark-up.

This isn't a client project, it's an experiment. Brian has merely exhibited something using some DIV's and clever CSS that most developers would never even try to attempt let alone even be able to pull off. An experiment doesn't need to be cross-browser compliant or practical, it just needs to prove something can work.

I've used SVG in production before and while it's generally well supported if you don't care about IE8 support, when it comes to hyperlinking and hover states an SVG can be your worse nightmare. Tonnes of people know about SVG, anyone with a copy of Adobe Illustrator can make an SVG image for web and embed it into a page.