There's a lot of misunderstanding about currency markets (obviously BTC/USD in this context). Arbitrage ensures stable prices across competing markets/exchanges. Automated trading adds liquidity, reducing volatility. All of this is good for market functionality.

As for market manipulation, if someone crashes the market with a large sale, ce'st la vie! If it goes too low (in your opinion) it will quickly resume to a stable price but now including the increase in supply (at the previous high price). If you don't like short-term movements in the market, don't trade in them - or better still, consider them buying opportunities. Vice versa.

This really isn't an issue IMO.

Second.

A fool and his money are easily parted. It will be sad when people fall for this should Bitcoin become more mainstream (to imply that all current Bitcoin users are AWESOME ;-). However, that this happens for IRL customers of IRL banks, it proves that IRL regulations don't help [much]. Education is the key to consumer safety here.

Not that big governments and central banks are exactly keen on improving financial education: they might understand how their big-spending racket works. Just add another bank or government guarantee to "protect" consumers. ;-)

P.S. Newbie mode sucks.

Which interview?

Lame restrictions. Long-time-reader first-time-caller who only registered to post on a thread to which I can finally contribute something meaningful. Not to take anything away from the need to enforce such restrictions.