Was Neil Young's 2006 tour with Crosby, Stills and Nash the last one ever? Sounds that way, based on what Young reportedly said from the stage last night in Philadelphia.

"CSNY will never tour again, ever," Young is quoted as saying during the first of two sold-out solo shows at the Academy of Music. He had been discussing a guitar, "given to me by my good friend Stephen Stills" before making this history-making pronouncement -- and then quickly adding, "I love those guys."

Crosby, Stills, Nash and Young stormed to the top of the album charts in 1970 with 'Deja Vu,' a recording that spawned a trio of Top 40 singles. CSNY then quickly scattered for solo projects, before trying to record a follow-up -- and failing -- several different times over the years. It would be 1988, with 'American Dream,' before Crosby, Stills, Nash and Young issued a second full-length recording. Another decade would then pass before the arrival of a third album, 'Looking Forward.' Among the quartet's most recent one-off appearances was a memorable stop at Young's 2013 Bridge School benefit.

Young certainly has enough on his plate, with or without a CSNY tour. In November, he'll issue two editions of his latest solo album, 'Storytone': one a solo version and the other with an orchestra. Young is releasing his second book, the car-focused 'Special Deluxe,' this month, too. He's also in the midst of a surprising split with his longtime wife.

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