Here are the top-ranked shows in Canada (for all persons 2+; all times ET), according to BBM, for May 17 to May 23, 2010.

Monday: Gregory House can’t seem to shake those nerdy sitcom stars: CTV’s The Big Bang Theory took top spot for the week with 2.72 million viewers, soundly defeating House, which brought in 2.545 million viewers. Last week, the NHL Playoffs on CBC took top spot with 3.247 million viewers, claiming Monday, Tuesday and Wednesday nights.

Tuesday: A singing contest replaced a hockey contest as winner of the week, with CTV’s American Idol claiming the top slot of the night with 2.484 million viewers. It was Idol‘s second-best finish of the week.

Wednesday: This was Idol‘s biggest night, earning 2.647 million viewers and claiming second spot overall for the week.

Thursday: The most-watched night of the week, Grey’s Anatomy on CTV claimed top spot and earned 3.014 million viewers. Hockey was far, far behind in second spot, with the NHL Playoffs earning 2.204 million viewers. Last week, Thursday night was claimed by Global’s Survivor: Heroes vs. Villains for its finale.

Friday: The NHL Playoffs on TSN were the highest-rated program for Friday night, with 1.332 million viewers on board. Last week, the top spot was claimed by CTV Evening News at 7 p.m., with 1.407 million viewers.

Saturday & Sunday: It was hockey night for most Canadians on Saturday and Sunday, with the NHL Playoffs taking the #1 spot both nights with 2.204 million viewers apiece.

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