The Splunk App for Vmware v3 requires a new install and is not an upgrade, and yes there is a fee to use that app. You can contact our sales team to discuss.
There are particular solutions where Splunk is dedicating tremendous resources to provide value to customers on top of our Operational Intelligence Platform. We are charging a modest fee in the case of the Splunk App for VMware so that we can continue this innovation as the technology improves/changes.
http://www.splunk.com/view/SP-CAAAH5H
