Mining difficulty has decreased
We will see. I bet on the BTC price decline, people are just selling all their miners (c.f. Ebay). Amateur miners gonna be very rare, which also means BTC hype is declining.
So no, people will not start mining again, unless we see a surprising massive price boom back to $800.
Some links:
[ul][li]SMS Might Sell Ross Ulbricht’s Bitcoins Below Market Price, Says Citi’s Steven Englander - http://www.coinspeaker.com/2014/12/03/usms-might-sell-ross-ulbrichts-bitcoins-below-market-price-says-citis-steven-englander/[/li]
[li]Bitcoin Price Decline Sparks Rare Mining Difficulty Drop - https://twitter.com/coindesk/status/540162982840643585[/li][/ul]
The only miners that will remain will be the ones making profit (mining farms where electricity is cheap, i.e. China or where the produced heat is sold). Which leads to BTC mining centralization. If we want to promote PoS with PPC, this is now the right time.