Craig HlavatyThe Phish of the Southwest and king of Houston's summer concert hill: George Strait​Online ticket broker StubHub.com released its annual list of America's Top 20 "Most Rockin' Cities" Friday, with Houston holding steady at No. 17 for the second year in a row. We probably would have been even higher - in several ways - if Vermont jam-band overlords Phish, who reunited this summer for the first time since 2004, weren't such pussies and booked some shows south of the Mason-Dixon line