If you filed a 2010 federal tax form early expecting a refund, and you got back more than you expected...?

...does that reflect the economic recovery act (which I believe was initially signed in 2008 and renewed by Congress for the 2010 tax year), aka a stimulus rebate? Current info at the IRS website does say something about most single filers being eligible for $400 maximum, but it isn't clear if it pertains to the 2010 tax year.