The release of the 2 Player Pong Game for PS3 and also the Homebrew Devkit using the Java Runtime for PS3 brings hope that a full on exploit for Homebrew on the PS3 can be found.
In the meantime this use of the Blue Disc Java Runtime means that at least Java Games are doable in Homebrew on the PS3 and on most any firmware/region version of the Console.
The next eventual step will some sort of emulator on the PS3 using Java and looking on Google you can see theres quite a few Java Emulators emulating a lot of systems, theres even a Java PSP Emulator for Windows being worked on, now imagine running PSP Games on your PS3 in time.