Let's Talk Bitcoin podcast - Interview with Adam Back, British cryptographer and hacker who invented HashCash, part of Bitcoin protocol. He worked with Satoshi and very rarely gives interviews.
He talks about problems with Bitcoin, privacy, anonymity, problems and fixes.... long but very interesting.
He talks about Zerocoin, Darkwallet, CoinJoin. If you've got some time... it's technical but worth a listen.
http://letstalkbitcoin.com/e77-the-adam-back-interview/