Wednesday's Grand, Super Duper, Last of three Uber finale episode of The Oprah Winfrey Show drew a 13.3 household rating in the metered market overnight ratings. That was the show's biggest overnight rating in 17 years.
That compares to Monday's 10.2 HH rating, and Tuesday's 10.7 HH rating.
To put that in recent context, for the week ending May 15, The Oprah Winfrey show averaged a 5.4 HH rating and 7.345 million viewers.
No official word from Nielsen on average viewership yet, but back of the envelope calculations by me put it in the 17-18 million viewer range.