How bad is the music industry's current slump? Billboard's new No. 1 album — the Grammy-winning soundtrack to O Brother, Where Art Thou? — sold just 159,000 copies. R&B singer Brandy's latest CD, Full Moon, debuted at No. 2 with sales of 155,000. Last week's champ, Alanis Morissette's Under Rug Swept, fell to No. 3 with 119,600 units sold.