It seems that many investors are battening down the hatches in case there's a flight to liquidity which could be caused by any number of things... Europe, China, etc.
Corporate America (the S&P 500) is sitting on over a trillion in cash, US banks are hoarding cash and neither seems interested in investing it at the moment. Perhaps there's a good reason for it? Since 2008 when the financial bubble burst, nothing's really changed and there's still a lot of things that need to bleed out before things are normal again. Even the US housing market, in certain spots has not yet bottomed.
Personally I am sitting on a tonne of cash on many fronts.