Amazon.comWith the centenary of George Gershwin's birth at hand, the tribute albums are thick on the ground. Standards and Gems is an agreeable if uneven addition to the pack, collecting material written for such Jazz Age warhorses as Lady, Be Good!, Oh, Kay!, and Girl Crazy. The gems (i.e., rarities) can be taken with a grain of salt. Indeed, it's hard not to wince hearing John Pizzarelli wobble through such undistinguished do-whacka fare as "Little Jazz Bird." Yet the obscure "Meadow Serenade," a Gershwinian version of the pastoral, is a charming discovery. And the standards, of course, are just that--indestructible melodies wedded to the wittiest lyrics of the era. Only a career curmudgeon could resist Dawn Upshaw's "Someone to Watch over Me," in which the soprano, emoting not a whit, delivers a crystalline (and, yes, classical) reading. There are some surprises, too. Audra McDonald's "How Long Has This Been Going On?" is no mother of all torch songs, but an exhibit of uptempo sauciness--and who but Ira Gershwin would have the nerve to rhyme "panties," "aunties," and "Dante's" in the space of a single verse? They just don't make them like that anymore. --James Marcus