There has been a mail thread on this topic in the FMW Forum and I liked the White paper on this. Couple of points from the people who replied to this:
In addition to being the strategic runtime for Oracle Fusion Middleware, the new product lines acquired from BEA, the Oracle Applications portfolio and the forthcoming Fusion Applications, Oracle WebLogic Server offers significant additional capabilities to the Oracle Application Server customer base beyond that which was available within Oracle Application Server including:
1. Runtime: Within the area of the core container, beyond the fully certified Java EE 5.0 compatibility, WebLogic Server extends the runtime in numerous areas including the Java Message Service (message ordering with unit of order, unit of work, scale out with distributed destinations and store and forward infrastructure, C and .NET JMS clients), Web services (conversational Web services, buffered Web services, asynchronous Web services, SOAP over JMS), built-in Tuxedo integration and runtime tuning (self tuning work managers) amongst others.
2. Development: Within the area of development capabilities above that in basic servers, WebLogic includes Java class FastSwap capabilities for fast test/debug cycles without server restarts, split development for tightly integrated IDE development, HTTP Publish/Subscribe Server for AJAX applications, filtering class loader to handle multiple versions of class libraries, Ant tasks for development, deployment and configuration automation and deep Eclipse and JDeveloper integration amongst others.
3. Operations and Administration: Within the area of operations and administration, WebLogic Server extends basic server capabilities in numerous areas including transactional and batch configuration, zero-downtime re-deployment, domain template builder and configuration wizard for simplified cloning, consistent scripting and command line tooling for all server configuration with WebLogic Scripting Tool, sophisticated lifecycle control over applications and the container, built in diagnostics framework amongst others.
4. High Availability: Within the area of high availability WebLogic Server extends basic core availability capabilities in a number of areas including clustered JNDI, whole server migration, service migration, high availability for singleton services
The white paper can be downloaded here.
