In these parts, it's not Christmas time until the man in the white beard says so. That would be Peter Nero.

For more than a dozen years, he has presided over an annual holiday show with his Philly Pops. Nero is stepping down at the end of the season, which means that the current run in Verizon Hall is probably your last-ever chance to hear Enescu, Glière and Mussorgsky as the pike, carp and whitefish of a giant gefilte fish of a Hanukkah medley. Nero's successor is not a pianist, which also suggests that if this tradition continues, the format won't feature a jazz pianist who somehow manages to be both erudite and haimish, with a little show-biz humor thrown in for good measure. Nero is the end of the line.

Take his Christmas adaptation of "Gangnam Style" (please). PSY's video has clocked 925 million hits on YouTube, and that's good enough for Nero. He put together his own version for Santa, a line of leggy young dancers and a Korean singer from the University of the Arts as Nero chimed in at the punch line ("Oh, Santa baby"). This, obviously, is what a 78-year-old Jew from Brooklyn can do when he really puts his mind to it.

Just when you're ready to throw up your hands at all the zaniness, Nero does something so interesting, so genuinely the work of an artist, that he leaves you unsure of who he really is. His arrangement of "White Christmas" starts off out in the cold, a disorienting snow globe of repeated patterns. The piano cadenza sounds like it could take you any place, and where it leaves you off is warming by the strings. It's a lovely moment, and the journey there exposes Nero's piano as more free-wheeling and inventive than Ahmad Jamal, and in a league of tastefulness with Marian McPartland in her prime.

In life, as at the podium, Nero free-associates, and the musical manifestations can be curious. Each show is a little different, but Sunday's included a gospel choir and Handel's Messiah. Count Basie and Mariah Carey tunes. And where else can you hear an arrangement of "God Rest Ye Merry Gentlemen" in the style of the 5th Dimension — with boychoir?

All traditions die. In Philadelphia, Christmas no longer arrives as Santa climbs atop a fire-truck ladder into a Market Street department store window, and next year it will no doubt come even without the jolly antics of Peter Nero. But it won't be the same.

The video below was posted to YouTube by user caitisgreat6.