Character mistake: When the high roller Ikachawa returns to The Tangiers, Rothstein said he's betting $1,000 instead of his usual $30,000, so when he won, it didn't feel like he had won $10,000 (10 $1,000 bets), but felt like he lost $90,000, alluding to the fact that betting 1/30th of his normal bets made him feel even though he was winning $1k a hand he was missing out on the other $29k, or losing that. At ten hands won, at $1k/hand, he really would have felt like he was losing $290,000, not $90,000 as Rothstein says.
Character mistake: When Marilyn asks Henry "Do they know they're not on the air?" her finger is pointing just below her face. In the next frame with the camera now facing the pair, her hand is down at her lap. (00:47:00)