In addition to the lack of memory, I was under the impression that RIM was no longer going to offer any future OS support for the 8830. Could be wrong but I thought I recalled reading that somewhere. If I'm incorrect please set me straight.
1). The 8330 is old, old, old and RIM do not want to support it. They want you to buy a new phone. If you want OS6 this is what yo must do.
2). The 83xx series had a really slow processor that is not fast enough to run OS6
3). The current crop of BlackBerrys have 512Mb of memory which is what RIM (the worlds tightwads of memory) regard as necessary to run OS6 properly. My 9700 has 256Mb and that does run OS6 but I am back in the "How much memory do I have left." scenario that I though I had left behind. The 8330 has 96Mb memory and that ain't enough to run OS6.
You will recall that only the 96Mb 8330 was ever able to run OS5 leaving millions of 8300, 8310 and 8320 owners stuck on OS4.5 with only 64Mb memory.
The bottom line. Forget OS6 on the 8330 because it will never even be developed for this phone let alone leaked or released.