Word came this week of Russell Janzen’s promotion to soloist at New York City Ballet. This dancer, who joined the company in 2008, has suddenly emerged as a new force in the company, a natural actor with a commanding presence onstage as welll as an expressive, assured partner. I missed his début in Balanchine’s Davidsbündlertänze last season, but by all accounts it was extraordinary for its depth and sensitivity. More recently, he infused the opening section of Balanchine’s Tchaikovsky Suite No. 3—one of those ballets you simply want to get to the end of—with new urgency. Suddenly, it mattered. In Chaconne, he manages to be both regal and light, and a great foil for the blazing Sara Mearns. He hasn’t done much, but somehow you just know he’s got a lot to give.