You should expect some carryover of continuing difficulty increase or relative stability for some time after a price collapse. Most Bitcoin hardware is pre-ordered in one way or another. Miners will be taking delivery of prepaid units for the rest of 2014 regardless of the BTC price. Even if the BTC price becomes abysmally low, miners will still continue to add their hardware to the network so long as it earns more than the cost of electricity (and maybe even if it earns less, if the miner is financially irrational).

However, we have seen some hashrate lost today, so there is some category of miner that is immediately sensitive to price.