I reached out to Unify2 a few weeks ago about their PowerView solution which they state provides “a comprehensive reporting/billing solution for OCS”. I was impressed with the offering and asked if they would share the deck so that I could include some screen shots in the blog post. Determine your needs and request a demo, I think they have filled a reporting gap in the product quite well.
Usage Trends by Modality
Usage-Based billing summary by Geography or Organization
Disclaimer: I know and have worked with at least 5 of the Unify2, Inc. employees when they were at Microsoft. Outside of this solution I am aware that Qwest, Eagleware and MindCTI are reported to have solutions but I have not seen them. Also we have samples in the Resource Kits and https://communicationsserverteam.com. If your company has a solution, please share the url and details to see a demo.