If you keep doing that, it will crash again, at least down to $15.
But certainly the bulk of the value remains from speculative interest rather than organic demand for the coins for use in commerce.
http://buttcoin.org/bitcoin-mining-rigs-fire-and-electical-h...
Also, being in China they are likely to keep a good part of the profit in BTC to use in services, since a lot is not allowed over there. This can kickstart a local BTC economy where it's needed the most.
Provisioning EC2 GPU instances and the like and writing the grammars.
If someone has the incentive to break into your wallet, all you need is a phrase long enough to make physical violence a better alternative for the attacker, and you're set, no need to make the phrase any longer.
Around 0.6% of all Bitcoin are known to be lost, so with unknown losses it could be 1-2%(https://bitcointalk.org/index.php?topic=7253.120)
Excluding the Pirate scam, 2.9% have been stolen. These are still viable, some are tainted since the receiver address is known. (https://bitcointalk.org/index.php?topic=83794.0)
A virus which deletes wallets instead of trying to exfiltrate BTC seems much easier to implement and would be pretty devastating for the currency.
Edit: there is no resistance upward right now on MtGox. $300k of buys would push to $24. $500k to $30. http://bitcoincharts.com/markets/mtgoxUSD_depth.html