I think you will find that Google does support product images.
Look at
http://support.google.com/webmasters/bin/answer.py?hl=en&answer=146750
Looking at the source of one of my product pages that has the rich snippets, I see the following.
<meta itemprop="image" content="" />
I assume that is put there my your rich snippets mod, but it is empty.
Steve