It’s been more than 15 years since Alvin Ailey died, and yet the company that bears his name is more vibrant than ever, says John Rockwell. “As this 2006 season opens, the company is showing signs of moving up to a new level. Its performances are enjoyed by teeming audiences nationally and internationally, with a steady, not to say backbreaking, touring schedule. Its dancers are better than ever, with the marvelous athleticism, vivid personalities and sleek sensuality the company has long fostered, now infused with the presence of starry newcomers.”