In his heavily publicized debut last night, CNN’s Piers Morgan Tonight drew 2.1 million viewers, 520,519 of them in the 25-54 demographic. Morgan couldn’t dethrone the reigning king in the 9 PM slot, Fox News’s Sean Hannity (2.4 million, 599,800 in 25-54), who had Sarah Palin on, but crushed MSNBC’s Rachel Maddow Show (1.1 million, 342,013), which had been Hannity‘s runner-up in the 9 PM hour. Morgan’s premiere, which featured an interview with Oprah Winfrey, came very close to the farewell episode of his predecessor, Larry King, who averaged 2.2 million for the final Larry King Live last month, and is head and shoulders above CNN’s primetime average, including Larry King Live‘s 674,000 viewer average for 2010.

Morgan is getting a great lucky break in his premiere week. A previously scheduled interview with British comedian Ricky Gervais, slated to air on Thursday, has the potential to become a big newsmaking event following Gervais’ much talked about hosting performance at the Golden Globes. Could Gervais do for Morgan what another Brit, Hugh Grant, did for Jay Leno, fueling a ratings upswing? And speaking of noisemakers, Morgan has Howard Stern tonight.