GALAXY S3 IS QUAD CORE.
i just upgraded today 23jun2012 my galaxy note 1.4dual core 2.3 gingerbread to 4.x .upgrade was ok. but phone becomes slow. before , eats only 300 to 500MB ram out of 800MB+. now it immediately eats 600 to 800MB making many hang ups.

i think its not good to upgrade to this OS. i heard that s3 has 2GB RAM, so its fine with s3, not for others with less than 1GB RAM.

everybody be careful. i hope i can reverse the upgrade(i did not back up also= so confident).