On paper, Greendaledoesn't sound like one of Neil Young's better ideas: a whimsical concept album-cum-community theatre piece that mixes his cosy view of small-town America--insular, sentimental, occasionally xenophobic--with well-meaning if woolly anti-corporate, pro-environment sloganeering. Such clarity of purpose rarely suits Young. Indeed, the eco-hymn "Be the Rain" makes After the Goldrushsound more gnomic than ever. But what Greendalelacks in mystique, it makes up for with love and eccentricity. Though his voice is thinner than ever, Young sounds more engaged than he has in years--certainly more so than on the sleepwalking slush of 2001's Are You Passionate--and the obvious pleasure he takes from his grand idea here is enough to carry you through the album's ropier passages. Young...