Here’s some good news for Galaxy S III owners who have been patiently waiting for an Android 4.1 Jelly Bean update, Jelly Bean AOSP port is already available for the international version of the Galaxy S3 version, the GT-I9300 model.
For those who don’t know, AOSP stands for Android Open Source Project, which means the Jelly Bean version developed for the Galaxy S III is based on the Google’s Jelly Bean open source code which basically means you’ll get stock Jelly Bean interface and experience without the added bloatware.
All thanks to Faryaab a recogninsed developer in XDA forums and there’s a detailed tutorial already available for anyone interested in installing Jelly Bean AOSP on the Galaxy S3 and enjoying a pure Google Android experience:
This ROM is built entirely from Google’s JellyBean source code. I’m actually working on my upcoming ROM “SuperNexus”. So I just compiled a pure AOSP JellyBean for the Galaxy S3 so i know that I can add support of it in my SuperNexus ROM. This ROM might only get 1-2 more updates because I will release SuperNexus very soon.
Do remember to follow the instructions to avoid bricking your device . For those daring enough, enjoy the stock Jelly Bean experience.
Instructions:

Downloads
Latest Build:
Google Apps:
[via XDA Developers]