It wasn’t the Super Bowl, but in terms of social-media buzz, Saturday Night Live’s 40th Anniversary show during Sunday primetime probably was as close to the big game as the late-night landmark will ever get.

All told, according to Nielsen, the show spawned 1.3 million tweets seen by an unduplicated audience of 9.1 million people during the show and for the three hours before and after. That’s a record for an episode of a regularly running series, Nielsen said. Those tweets were sent by 449,000 people, a big but not extraordinary number.

It was, however, very big numbers for a regularly scheduled series, enough for Nielsen to declare it a record. Special events such as the Super Bowl and the Grammys can rack up vast numbers (the Grammys spawned 20.9 million tweets, but that was worldwide, given the international reach of music). but episodic TV seldom gets a big enough audience in the moment to come close to those stratospheric numbers.

TWayne's World SNL40 Top 10he SNL40 show already has proved to be a sweeps-month ratings bonanza for NBC, but the social strength was a big win on top of that. There were plenty of factors helping out, like the fact that the show itself ran 3.5 hours long and during primetime on the week’s biggest TV-watching night (more time to tweet, and more bits to tweet about, at a time of night when audiences are bigger and awake).

It also had a red-carpet preshow that featured a few tweet-worthy bits, including that Jim Carrey question about Brian Williams’ location, asked of a nonplussed Matt Lauer and Savannah Guthrie as Tina Fey looked on.

The show attracted the participation of plenty of Twitter powerhouses too, including Taylor Swift (52.6 million followers), Justin Timberlake (41.8 million), Jimmy Fallon (21.4 million), Neil Patrick Harris (13.6 million), Kanye West (11.2 million) and Jerry Seinfeld (2.7 million). Even old-old-school comedian Billy Crystal brought his 536,000 Twitter followers to the party. And the tweets didn’t have to say much to get thousands of retweets and favorites:

Maya Rudolph, Kristen Wiig, Alan CummingTwitter itself helped out, setting up its customized photo-sharing booths (called Twitter Mirrors) backstage, on the red carpet and at the pre-party, so celebs could take individual and group shots that then were posted to SNL’s Twitter feed, @SNLNBC, like this one to the right featuring Kristen Wiig, Maya Rudolph and photobomber Alan Cumming.

Helped by the search hashtag #SNL40, the episode was, no surprise, the biggest unique audience for the show this season and set a record for most Twitter TV impressions ever for the show.

That latter record of 188 million tweets seen isn’t quite as impressive when you remember that Nielsen has been measuring Twitter impressions for TV shows for only a couple of SNL’s 40 years, but it’s still a testament to the show’s social-media reach, decades after it launched, on a big night of celebration.