When you first try and load a Java application (eclipse, run mvn commands etc) Lion prompted you to download a JRE/JDK. From my understanding this is still Apple's version of Java and not OpenJDK. Will Mountain Lion still have Apple's Java available the same way or will it prompt you to download OpenJDK?
It prompts you (just tried to open Aptana). I let it install and
java version "1.6.0_33" Java(TM) SE Runtime Environment (build 1.6.0_33-b03-424-11M3720) Java HotSpot(TM) 64-Bit Server VM (build 20.8-b03-424, mixed mode)