Elvis Costello - NorthAre Diana Krall and Elvis Costello morphing into each other? While Krall inches further into pop, her future hubby has plunged headlong into jazz. Costello’s latest album sees him working with saxman Lee Konitz, the Jazz Passengers and the Mingus Big Band (along with usual suspects Steve Nieve, Pete Thomas and classical cohorts the Brodsky Quartet). Piano ballads like “I’m in the Mood Again” and “When Green Eyes Turn Blue” are tailor-made for Ms. Krall and good chemistry for a marriage made in musical heaven.