The risks seem higher on the other side -- that many of the factors holding down inflationary pressures will prove temporary, that the rebound of productivity necessary for higher sustainable growth will not occur or not prove robust and durable.
The drop in oil prices has: 1)  heightened deflation pressures in the EU and Japan,  2)  led to reduction in capital expenditures in the US that now threatens to soften economic growth and inflation in the US, and,  3)  caused some emerging markets to also be leery of the adverse growth effects if deflation becomes more pervasive.