From the Big Picture:
The SP500 bounced back to the 50 day moving average, but volume has been a bit soft (i.e. low). It looks like price action at the 1300 level will dictate a resumed uptrend, downtrend, or range bound market.
Sources:
S&P500 Update
Barry Ritholtz – The Big Picture
http://www.ritholtz.com/blog/2011/03/sp500-update/