Cat Power’s been napping. By the time her new album, The Greatest (not a greatest hits record — boy I’m sure her label friends will tire quickly of repeating that mantra), hits stores in January three years will have passed since her last album. Not bad really. The space between her last albums lasted about four years. I should cut her some slack. The wait is always worth it. This time around she taps the Memphis soul scene for her backing musicians, with, among others, Al Green’s boys, Teenie Hodges (who co-wrote “Take Me to the River” with Green) on guitar, and Leroy “Flick” Hodges on bass. Judging from the small sample offered, Chan Marshall may be on her way to creating a timeless work of art.