Alan Greenspan, former Federal Reserve chairman and economic 'Maestro,' spoke this morning at a packed Radio City Music Hall. In a very Wall-Streety charcoal grey suit and red tie, the man who presided over two decades of nearly uninterrupted growth in the U.S. seemed relaxed and happy -- there to bask in his glory, not raise the alarm.

That doesn't mean he had all good news to tell to the 5,000 attendees of the World Business Forum. Greenspan had a few basic concerns (which will be familiar to those who have heard his latest thoughts as he makes the media rounds to promote his memoir, "The Age of Turbulence"):

* The housing market is going to continue to decline. It's simple really -- there is a lot of unsold inventory of newly constructed homes still coming on the market. Builders will cut prices to sell and that will drive down the broader real estate market. How significant will the declines be? He wasn't sure.

* The odds of a recession are between 30% and 50% (or 42.35%, Greenspan said as a joke). In March he thought the odds were only 30%, but following the crisis in the credit markets, he now thinks it could be as high as 50%. The deciding factor will be how the stock market holds up. Since it is recently hitting new highs even as economic growth slows, things are looking pretty good.