Btc-e, one of the largest BTC/FTC exchanges, increased the confirmation requirement to 100 blocks (over 4 hours) completely countering Feathercoin’s quick confirmation advantage.
This is why I'll tell anyone who will listen that keeping funds (any funds, Bitcoin, Litecoin, etc.) on an exchange that also deals with a currency other than Bitcoin is taking a big risk.
Your Bitcoins Are Not Safe At Alt-coin Exchanges -
http://www.bitcoinmoney.com/post/6231627Yep, and I'd generalize that insightful article and your statement even further: BTC are not safe anywhere whose private keys you don't control. Ultimately, the "altcoin attack" is just one risk among a potentially infinite list of catastrophes involving exchanges and hosted wallets, be they BTC-only or multicoin. Mirroring goldbug wisdom: if you don't hold your BTC, you don't own your BTC.