Krall: seven albums; two Grammys.
Costello: 24 albums; one Grammy; inducted into the Rock and Roll Hall of Fame this year.
Two old souls: he, the kind of guy who, at the age of 19, could write the lyric "Bad lovers face to face in the morning / Shy apologies and polite regrets"; she, the kind of gal who, with that beguiling, oboe-rich alto, already sounded like an accomplished contemporary of Rosemary Clooney's or Ella Fitzgerald's on her earliest recordings. That these two paragons of Cole Porter urbanity and grown-up mischief should find themselves engaged, well, it's delovely, wunderbar, the top, magnifique, and whatever other Porter allusion you care to deploy. We'll leave it to the likes of People and Us to speculate about babies on the way, but already, we can report, there has been some cross-pollination: Elvis, a longtime guitar man, is now singing while playing piano, and Diana, a longtime "interpreter", is now writing her own songs.