I didn't get to see Bill Maher's Religulous, but apparently a lot of people did. It was on 502 theaters, and earned $3,500,000. For those keeping track, Ben Stein's Expelled earned $2,970,848 on its opening weekend, and was showing on 1,052 theaters. In other words, it earned less money despite showing on more screens.
Its reviews are kinda mixed, but it should be worth seeing.