Oracle JDeveloper is the main development platform for Oracle's tools. The core IDE exposes an API that other teams in Oracle use to build extensions to JDeveloper. BPEL, Portal, BI and other components of the Oracle platform all build their design time tool on top of JDeveloper. The same IDE platform also serves as the basis of another Oracle product, SQL Developer, which is geared specifically at PL/SQL and database developers.
It is statements such as these that continue to throw confusion into the discussion. Because, after all, yes, Oracle has an IDE (JDeveloper), just like Sun has an IDE (NetBeans IDE). And, yes, Oracle has a development platform (JDeveloper), just like Sun has a development platform (NetBeans Platform).
If you like, that's where the story ends.
However, I'd like to see examples of military, financial, and geological applications on the JDeveloper platform before the story ends for me. Applications such as Agile Client by Northrop Grumman:
Or, in fact, applications like any of these:
Yes, Oracle JDeveloper is a platform. But only if you're interested in creating development tools. Not if you're interested in creating sales systems, for example, such as the Sepix Sales System:
The NetBeans Platform doesn't simply offer APIs for extending its IDE (as JDeveloper does). It offers APIs for creating your own desktop applications, of any kind at all... and financial institutions, military organizations, oil & gas software providers, retailers, and on and on, have been making use of it for MANY years already. And making money off it too, by selling their software created on top of the NetBeans Platform. Typically, all these applications are very large, since the NetBeans Platform's main contribution is modularity/scalability, which is a concern specifically for applications that are either (1) large or (2) will potentially be large at some stage in the future. (And unlike Eclipse RCP, you get to keep your investment in Swing, as a brand new interview with an ex-Eclipse fan shows and this 3rd-party slideshow confirms.)
The word "platform" has been used and abused for so long, that the complete manifold differences between NetBeans Platform and the JDeveloper platform should not really be news. But it's worth mentioning for those who take pride in making superficial comparisons between apples and oranges. Oracle has nothing, in any shape or form, like the NetBeans Platform. The latter does not compete with any of the former's products in any way at all.