Jimmy Fallon simply excels at these skits. Here he’s John Lennon in a witty take from last night’s show. How would the Beatles embrace social networking? Remember, they licensed “Baby You’re a Rich Man” to “The Social Network for well over a million dollars. (That was a Showbiz411 scoop a couple of years ago.)

Seth Meyers’ debut  tonight as host of “Late Night” signals Lorne Michaels’ full takeover of NBC’s late night schedule. Michaels has Jimmy Fallon’s “Tonight” show and “Saturday Night Live.” Fallon debuted last week to great reviews and huge ratings. Now comes Meyers, straight from head writing “SNL” and doing the Weekend Update for years, along with plenty of stand up comedy.

You can’t predict a golden era, but maybe we’re starting one. The combination of Fallon and Meyers is sort of brilliant. Meyers also brings with him “SNL” key player Fred Armisen as leader of his band. On tonight’s debut, we get a glimpse of how much Armisen is value added just in a little repartee at the start of the show about Fred’s supposed new series called “Recent History.” Watch Seth playing with the idea, and then Amy Poehler pick it up later.

But the show is about Seth Meyers, who I really did hear — some 18 months ago– would be Kelly Ripa’s permanent co-host in the morning. He had no trouble playing a young Regis and engaging the audience. (Michael Strahan has done fine, too.)

Meyers is made for “Late Night.”  He’s got to be fun but he doesn’t have to go big big big like Fallon. This isn’t the Tonight show, after all. “Late Night” gives Meyers the ability to get serious sometimes, be on a smaller scale, and still get in a lot of trenchant observations. His opening guests are Poehler, whom he describes as his “best friend” or “close friend,” and you know he really means it.

Poehler is followed by Vice President Joe Biden, who came to the studio Monday night with a huge contingent of Secret Service. He and Poehler had history from his appearance on “Parks and Recreation.” Meyers, rather than get into anything heavy, played off their past. It worked pretty well. Biden proved to funny enough. The studio audience enjoyed him. The Secret Service agents never cracked a smile. The trained German Shepherd attack dog, whose named, coincidentally was Seth, slept through the whole show.

Musical guest is A Great Big World, featuring Ian Axel singing their big hit “Say Something.”

Meyers makes the most relaxed, confident debut ever as a talk show host. Fallon at least had five years of “Late Night” to prepare him for the Tonight show. Meyers just steps into it, and scores. There are some things to tweak, including a very cluttered set that contains not the most interesting furniture. There is no couch. The chairs provided for the guests look uncomfortable and, dare I say, cheap. But those things are minor. The set also has no reference to New York, although the studio does. But you can’t see it unless you’re in the studio.

I can’t wait to see how this week unfurls for “Late Night,” and how Meyers secures the show in his own image.

The end of season four of “Downton Abbey” has lots of little inside jokes. Just as Elizabeth McGovern got to utter the word ‘ragtime’ a few weeks ago (she was nominated for an Oscar in that movie), Maggie Smith had a similar moment tonight in the final 90 minute episode. When the Dowager Countess said she felt she’d spent the whole night in a whodunit, she might have been thinking of “Murder by Death” (1976) or “Death on the Nile” (1978). She was in both whodunits to much acclaim.

Creator-writer Julian Fellowes had a lot of fun introducing the scandal plagued Prince of Wales who would one day become the resigned King of England, aka the Duke of Windsor. The Crawleys go to great lengths to spare the Prince from another public scandal involving his mistress, a married woman. When it was all resolved, one of the Crawleys observes that this won’t be the last time Edward will be in trouble. Indeed, not. Mrs. Simpson is still more than a decade away.

Shirley MacLaine and Paul Giamatti guest-starred as Lady Cora’s (McGovern) mother and brother, the Levinsons. They are described as incredibly wealthy, and we know they’ve bailed out Lord Grantham a couple of times. They are also probably Jewish and modeled on the Rothschilds. This is never mentioned. But the Dowager Countess sneers at them so, and not just because they are American. MacLaine seemed more at ease this time in Downton. Giamatti felt like he’d been on the show all along. He was an easy fit, and will probably get an Emmy nod for his work. He is just damned good at almost everything he does.

I don’t know how Julian Fellowes does it, and believe me I’ve asked. He writes all the shows, keeps all these characters straight, and mostly on track and true to their personalities. It’s sad to see Ivy leave for the U.S. but it’s time for new servants and kitchen help. One of the best lines of the night came from Daisy, who told Giamatti’s valet: “I don’t get excited.” The glaring differences between the Brits and the Americans is something Fellowes loves playing with, language especially, as evidenced by the Dowager Countess’s shock at almost every new phrase she hears.

Because Season Three had the two big deaths, Fellowes ended Season Four sweetly, with Mrs. Hughes and Mr. Carson hand in hand tip toeing into the sea (the future). What a lovely note. But Season Five will obviously address Edith’s situation with the baby and Gregson; Mary’s decision on a new mate; and how Branson will grapple with moving on but staying part of the Crawleys. January 2015 seems like eons away.

Great show Friday night on Jimmy Fallon with special guest Justin Timberlake. Here’s the video take out of the night: