If anyone has that U.S. bank info for btc-arbs, feel free to PM me it. I'd like to see if any of the info matches up with any previous projects. Also the 100,000 bitcoin address, are we sure that it isn't a mixing service or some sort of bigger exchange wallet? I would literally be shocked if btc-arbs was able to steal 100k bitcoin. If that was the case, I feel we should have seen some bigger whales post here about their deposits or at least more people. I personally don't think they ran off with more than a million USD or so in bitcoin.
100K BTC would far exceed any investment needed for arbitrage. If the website received anywhere near that, I would expect that they would stop accepting new accounts. Otherwise, they would receiving funds that they could never use, and (if they ever actually tried to conduct any real arbitrage) it would dilute the profits of existing investors. There's no reason to accept any more funds than that, even if the host was planning to run a scam, other than pure greed.
Personally, I would stop accepting new funds before hitting 10K. But then again, I'm honest.
Everyone should file a police report for their losses. Even if the police never look at it, it will be helpful when filing your taxes because you can subtract that loss from any bitcoin profits. If the reader doesn't intend to report bitcoin on their taxes, then it could still be useful in case the tax authorities find out (like from your bank) and provide protection in an audit.
Regarding the banking connections of Btc-Arbs, anyone who sent or received funds via their bank should contact their bank and have any sort of flag or tracer placed on the account if it is possible. It may never result in a successful lead, but the point is that the person who stole the money can't run off with total impunity.