MINYANVILLE ORIGINAL With the White House and Congressional leaders now in the heat of fiscal cliff negotiations investors chose to err on the cautious sides with stocks trading just slightly up on the last day of the trading week.   "I doubt we'll see anything concrete for quite a while " said Stephen Guilfoyle US economist at Meridian Equity Partners of the budget discussion according to The Street.. "I am certain that both sides will come out and say something positive because that's their job. They're going to make their constituents think they're working for them and they're trying ...