This is something I came to know while working with Weblogic for past few years. Over the years weblogic has developed quite a bit from one of its oldest version 6 (formerly known as BEA and before that known as Aqualogic) to Weblogic 12 (currently known as Oracle weblogic).
David Moyes might have left Manchester United in a mess this year (2013-2014), but oracle has done its bit to enhance Weblogic for its betterment. The most stable version currently in industry standard is 11g (10.3.6). Forgive me for showing my untiring effort to link Football to Weblogic, which are no way related, but one more expensive player bought on board by Oracle is Sun Java. And as a branch of Oracle Java is growing very fast and although Java 6 is considered as an industry standard now, there is already a new version of Java 8 already released in March 2014.
Now, naturally the question is where am I leading you to? The point I am trying to make is, the version of Java that comes for the latest Weblogic is still Java 6. Although you can use Java 7 in weblogic 12c (http://docs.oracle.com/cd/E24329_01/doc.1211/e24492/jdk7.htm), as of now we haven’t seen Weblogic using the full potential of the new Java versions. All features available might not be of use, but features like new concurrent Garbage Collector , improved compiler warnings etc would mean a vastly improved Weblogic application server with less and less memory issues for heavy enterprise applications.
And the latest in this is Java 8 which boasts of a very small JVM of 3MB. These features combined with the new improved weblogic GUI, security features gives enterprise applications a huge boost in terms of performance and ease of handling. What I am looking forward to is coming days with a complete package having the latest version of all the products required for enterprise application development. A Language (Java),an Application Server (Weblogic), a database (Oracle Database) and an IDE (NetBeans). This might act as a Commercial Of the Shelf (COTS) product for oracle and would standardize the process starting from development till deployment. Although this might sound as taking away the flexibility of the individual options that you can have but it is more to make an industry acceptable standard for enterprise architecture while free lancers and open source community continuing their adventure to explore new avenues and improve the standard in future.