Both WebLogic and Coherence are pure Java, (although both have native code accelerators available for various hardware & OS combinations, such as the Oracle Exalogic engineered systems).
"Natively integrated" is referring to the "native functionality" of the products. Starting with this release, you can use WebLogic's management infrastructure to manage a Coherence data grid, including:
* You can package a Coherence application into a "grid archive" (.gar) file, and deploy it using the WebLogic 2-phase deployment technology, thus creating a data grid running that application;
* You can drop that same .gar file into a Java EE application (e.g. an enterprise archive, or ".ear" file), and WebLogic will use its 2-phase deployment to deploy both a Java EE cluster (on WebLogic) and a data grid (on Coherence) with the necessary application components deployed to each, and with the two tiers automatically wired together.
* You can use all of the other functionality of the WebLogic management framework for Coherence, including provisioning ("node manager"), deployment, monitoring (WebLogic console), configuration, patching, diagnosability, and even scripting (using Python to do all of the above!)
So yes, it's a bit more than just a class path change :)
p.s. In the interest of full disclosure, I do work for Oracle, on both the WebLogic and Coherence products. My comments are my own, and do not necessarily reflect the views of my employer.