The better "risk on" sentiment has helped to push the AUDUSD higher.
That move has the pair currently trading just above a downward sloping trendline and 100 hour moving average near the 0.7262 level. The price is trading at 0.72674 as I type. The AUDUSD has not had an hourly bar close above its 100 hour moving average since September 10.
Although higher and trying to make a break into a more bullish bias, the risk from the FOMC is still elevated. There is a lot of uncertainty from the taper (when will it start), to the dot plot (which showed most Fed members looking toward 2023 for the first hike).
A more hawkish of Fed should be more bullish for the dollar. The movement of the equity markets can also be an influence and a wildcard after the decision. If the stock market can weather a more hawkish Fed, the "risk on" flows may continue helping the AUDUSD. However, if there the stock markets start to give up their gains, the AUDUSD could head back to the downside.