Few books released so far on 12c features or includes 12c Features, but all are not India (Asia) editions so they might be expensive, Watch out for this books in Flipkart and you may get for lesser prices once they get released here in India.
12c New Features book from Robert Freeman As usual
http://www.amazon.com/Oracle-Database-12c-Features-Press/dp/0071799311/ref=pd_sim_b_5
Rman Recepies from Arup Nanda & Darl Kuhn & Sam R Alapati
http://www.amazon.com/RMAN-Recipes-Oracle-Database-Problem-Solution/dp/143024836X/ref=pd_sim_b_2/192-0873658-0016931
On RAC & its Internals, Riyaz's book
http://www.amazon.com/Expert-Oracle-Syed-Jaffar-Hussain/dp/1430250445/ref=sr_1_fkmr2_1?ie=UTF8&qid=1374175578&sr=8-1-fkmr2&keywords=expert+rac+practices+12c
Martin Bach's Oracle 12c Consolidation
http://www.amazon.com/Expert-Consolidation-Oracle-Database-12c/dp/1430244283/ref=pd_sim_b_6/192-0873658-0016931
-Thanks
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