On his six solo albums since the first X hiatus in 1988, John Doe has created a Great Americana Songbook. An explosive rocker with an insightful ruminative bent, Doe uses his time away from the band to explore wide-ranging emotions and vivid scenarios, populating his songs with the lovelorn, the vagrants and the trod-upon but also with their fair share of optimists. It's his best solo work yet, mostly because he peoples some of his finest and most detailed songs with a cadre of sympathetic colleagues. Neko Case duets over the dry groove of "Hwy 5," while Cindy Lee Berryhill harmonizes on the delicate "Repeat Performance" and "Your Parade." Kristen Hersh chimes in on the speeding, Dylanesque "Ready," and Dave Alvin and Grant Lee Phillips show up for the cutting garage rocker "Heartless" (as well as for the dusty album-opener "The Losing Kind"). "Ready," Doe's paean to absent friends, is peopled by ghosts, including Elliot Smith. Forever Hasn't Happened Yet as pretty as the aching "Worried Brow," as gritty as the bluesy "There's a Black Horse" and as soaring as the cranking "Mama Don't."