Yes, Revive Adserver is the direct successor of OpenX Source version 2.8. You can upgrade from OpenX Source to Revive Adserver, and retain all existing data about advertisers, campaigns, banners, websites and zones, including all of your existing statistics.
Please have a look at some other frequently asked questions.
This is good news. I’d been bemoaning the utter mess that was OpenX and trying to figure out where to even get started with fixing the code. Thank you, thank you, thank you, thank you, thank you, thank you.