It not only take care of the VirtueMart pages but also take of your general Joomla Pages and Articles. You can even using the plugin in the site which does not use VirtueMart.

It's a FREE plugin can be downloaded and used by everyone without any limitation.

Compatible to Joomla! 3, Joomla 2.5, VirtueMart 3, VirtueMart 2.6 and VirtueMart 2.0.

Detailed Product Description: http://www.virtueplanet.com/blog/vm-og-meta-tag-joomla-plugin/index.php

Free Download: http://www.virtueplanet.com/category/10-vm-og-meta-tag-plugin

We have installed this plugin on our VP ProMart Template demo site. Check the source code of the site to see the OGP Meta Tags on any page. Click on the Like button on product details page and you will find the product details with correct product image in your Facebook timeline.

Credit : https://forum.virtuemart.net/index.php?topic=111306.0