Update on Confidential Transactions (CT) by Greg Maxwell: tl;dr Previously CT txns are ~16x size of normal txns. New breakthroughs by Benedikt Bünz and Jonathan Bootle results in only a ~3x size increase. CoinJoin can combine txns to make this negligible!
anyone who was interested in seeing confidential transactions make their way into Bitcoin will be excited by this paper with a much more compact range proof for CT. Greg Maxwell made a post explaining the context on bitcoin-dev list
Updates on Confidential Transactions efficiency
I wonder what kind of future privacy focused alts will have when Confidential Transaction get implemented in Bitcoin.