Although bitcoin addresses are composed of randomly generated hexadecimal characters, which are unrelated to one’s id, anyone can see each and every transaction on the public ledger, so the flow of bitcoins from an address to another along the blockchain is visible to everyone. Solely, the hexadecimal characters of a given address can never be used to identify the person using it to send or receive bitcoins.
http://www.newsbtc.com/2015/11/27/airbrushing-your-bitcoin-transactions-bitcoin-mixers-and-coinjoin/These kind of info-articles (which recycle things known for ages - the sources named consist of 2 bitcoin wiki articles) shouldn't really be passed off as news