The Massachusetts Taxpayers Foundation, a generally reliable fiscal prognosticator, delivered its state revenue forecast this week. As MTF president Michael J. Widmer aptly put it, "Not surprisingly, the picture is bleak. For the current budget year, fiscal 2009, MTF predicts tax revenues will total $19.4 billion, $900 million less than the administration's latest forecast. Worse, MTF predicts a decline in revenues to $18.6 billion in fiscal 2010. Fiscal forecasting is a mix of science and art, to be sure. However, the MTF figures - based on trends in employment, personal income, capital gains, sales taxes and corporate profits - demand serious consideration.