What does it say about today's music climate, when the only way a legend like Willie Nelson can nab some airplay is by teaming with a younger, more commercially viable artist? "Beer for My Horses," an insipid hit duet with Toby Keith a few years back, set a troubling precedent. Co-produced by Kenny Chesney, Moment of Forever launches from that cynicism. But nothing the former Mr. Renée Zellweger throws into the mix can distract from Nelson's everyman vocals. Even the occasional horn blast fails to ruffle the placid surfaces these semi-acoustic performances are built on. The always-versatile Nelson sounds just as comfortable brooding over Dave Matthews' "Gravedigger" as he does hitting the honky-tonk in Guy Clark's "Worry B Gone," a pro-pot tune sung with Chesney. And Randy Newman's solemn "Louisiana" takes on renewed relevance in the wake of Katrina. Nelson's originals — especially the timeless "Over You Again" — are nearly as good. Nobody makes music that sounds so effortless.