SPY went ex-dividend December 17th, 2010. The payout will be $0.6528 per share. The paydate will be 31-January-2011.
In premarket on the 17th SPY was trading around 124.17, after closing at 124.82 in regular trading Thursday. It looks like some poor soul had a buy order in at 124.74 that filled in the pre-market—ex-dividend day drops at the beginning of trading are one of the dangers of standing limit orders.