Other alternatives, according to NAB, "remain an extension of the low level of rate language out from 2014 and moving from a date to being conditional on economic activity; on its own, this would be disappointing. In conjunction with purchases it might be more powerful. The lowering of interest on reserves appears to be a less favourable choice."
Looking at the possible USD performance, "is likely to remain under pressure, and that leaves AUD/USD above 1.05" NAB suspects. However, a final advice of prudence is given by the bank: "We may have to wait until Jackson Hole before the market really changes its mind, again."