USDJPY - Is the Yen soon to be under attack again?

After Japan's recent economic results the BoJ is back in focus, and we're starting to hear a little noise surrounding the Yens recent recovery against the western currencies.  We've seen a good 700point rebound in it from its recent lows, but the question is now, is it sustainable?

Sales tax hikes are due to increase from 5% to 8% by April 2014 in order to tackle the monstrous government deficit that the country is currently in an ageing population (on the 09/08/13 the government debt passed the 1 Quadrillion Yen mark for the first time ever, thats 15 zeros after the 1 to you and me!).  This should really put a dampener on consumer expenditure and with business investment on the decline some people are questioning whether the PM is actually going to follow through with the original plan.