The National Gallery has done it again: a small but perfectly formed exhibition in their little Room 1, now a by-word for intelligent show-making. Something new, something revelatory, something profoundly beautiful – what more can the gallery-goer ask? The Ashcan School is not widely known outside the USA, and I can think of no better introduction than this dozen-canvas-strong showing of some of the highlights (and, it must be admitted, a couple of low-lights as well).

Hot on the heels of the Pet Shop Boys’ foray into ballet for Sadler’s Wells next month, it’s revealed that Sir Paul McCartney has composed a ballet for New York City Ballet, a love story called Ocean’s Kingdom.

Scheduled to premiere on 22 September, the four-act ballet so far has 45 minutes of music, and a cast of around 40. The New York Times reports that the first act is having its first run-through next Thursday at the Lincoln Center, NYCB’s home stage.

February is guitar month in New York City. Synchronicity rules at those two giants, the MoMA and the Met. At MoMA, Picasso: Guitars 1912-1914 shows his austere guitar paintings, collages and drawings - often using newspaper, wallpaper and sand - as well as constructions of guitars made of cardboard and one of sheet metal and wire. “What is it? Painting or sculpture?” asked snooty visitors to his Paris studio. “It’s nothing, it’s el guitare,” Picasso, who didn’t play an instrument, is said to have replied.

From a guitar by Matteo Sellas dating back to Germany before 1630 to one made in New York by John Monteleone in 2008, the Metropolitan Museum of Art’s Guitar Heroes exhibition is will go down as the longest guitar solo slot in history. Including one of the four surviving models by Stradivari, it monitors the guitar’s development in Italy and the instrument’s migration across the Atlantic. Angelo Mannello, born in Italy, made the mandolins seen here in America. It is clear from this gallery, which includes a bespoke instrument made for Paul Simon, that the skill exhibited by the great guitarists is no less an attribute of the craftsmen who design and build the instruments they play.

I didn't realise how much I liked dirt. Especially New York dirt. I was going to do a rant about boutique designer hotels, which seem ubiquitous in Manhattan. Major case in point: the Gramercy Park Hotel, where I used to stay in the Nineties and Noughties. It was independent, a bit scruffy, with a great bar full of artists and rock'n'roll types and other degenerates, a perfect location and cost about a hundred dollars a night. Last time I looked it had been ponced up – fish tank in the reception, a Buddha, fancy doorknobs and good-looking but no doubt useless staff. Clean as a whistle.

Metcentric New Yorkers tend to think an opera hasn’t achieved classic status until it arrives at their vast inner sanctum. Whereas other cities worldwide know that the inimitable Peter Sellars production of grand opera’s last masterpiece (to date) has become a virtual brand since its 1987 Houston premiere. John Adams's first, and biggest, opera was an obvious here-to-stay triumph at the Edinburgh Festival the following year, and its strengths become more apparent with the passing of time.

If the jewel in Sky Atlantic's crown is the award-guzzling Boardwalk Empire, great things are also expected of its new cop-opera Blue Bloods, judging by the number of trailers spattering the Sky networks. It's the Dynasty of law enforcement, chronicling the relationships and travails of the Reagan family of New York.

When the spotlight caught Teddy Thompson in profile last night it seemed to capture the physiology of an old-school country icon: tall and lean, his pale, angular face appeared all the more classically archetypal jutting out from his jet-black clothes. He certainly looked the part. By the end he had proved – to a degree far beyond any evidence presented on his recorded work - that he could sing it, too.