After Android 4.1 Jelly Bean can be ported to HTC One X (read : Tutorial How to Porting Android 4.1 Jelly Bean to HTC One X). Now, the Developer have ported Android 4.1 Jelly Bean to Samsung Galaxy S3. It's a good news for Samsung Galaxy S3 users, because the official update to Jelly Bean will be expected arrive at Q4 2012. But, now you can try Jelly Bean on your Samsung Galaxy S3 more early using this ported method.
As we know, every ported device always have some bugs which may ruin your mood to port Jelly Bean rom to S3. WiFi, bluetooth, NFC, Camera, Audio, storage and more will not work. If you interested to try it, please note that this is not the official update for Samsung Galaxy S3 and the process, least probably, may brick your device. We are not responsible about anything that may happened on your phone.
If you interested to port your device, You can proceed to try it here.