Retail may dominant the shortened trading session (markets close at 1pm) as millions of Americans head out to snag deals on Black Friday. Talks are ongoing among the Troika -- the ECB, EU and IMF -- over changing Greece's deficit targets prior to handing out the next tranche of aid. Canada's central bank officials have made comments in the past hinting that some form of monetary tightening may be necessary, a strong CPI number may lend credence to that view.