After updating my Samsung Galaxy SII to Jelly Bean a couple of weeks ago, Samsung pushed even newer firmware (I9100XWLSD) to my phone which is the best of all official Samsung ROM’s to date: with the update JuiceDefender was able to squeeze over 50 hours out of my Samsung Galaxy S II battery:
As Samsung also released Jelly Bean kernel sources, maybe the great Cyanogenmod-team can finally also push out a stable version of Cyanogenmod 10 for the SGSII?