On the second and final day of Jay-Z's Budweiser "Made in America Festival" in Philadelphia, conversation remained centered on its host. After bringing out Kanye West and most of his G.O.O.D. Music crew on the first night during his headlining set, the Brooklyn emcee returned on Sunday, joining Pearl Jam for an airtight, riffing take on his Black Album cut "99 Problems," a version of the song only comparable to a 2004 collaboration with Phish.