This was the second largest hack after Mt.Gox! Hell, there hasn't been any news on how the "hackers" got in. For all we know the same scenario could repeat itself. The prospects for Bitfinex are quite bleak at this point. I loved trading on there for many years!
Despite good-faith efforts made by Bitfinex management to restore investor confidence, volumes on the exchange are currently a small fraction of what they were prior to the monumental theft. Data from BitcoinCharts.com shows the drastic drop in volume on the Bitfinex BTC/USD pair after the hack:
http://www.razor-forex.com/2016/09/digital-currency-exchange-bitfinex.htmlWell no kidding the trading volumes are going to be smaller, you don't lose a ton of money and then suddenly have everyone flocking back to the exchange that collapsed once it is up and running again.
If they can keep the exchange running without getting hacked again, then some investors might return, but it will take a long time to recover from what happened.