Things have certainly been changing for Joe Satriani. Suddenly a lot of people besides a few musicians know his name, have heard about his awesome chops, are picking up his first record, Not of this Earth. Which must be why, on this hot and muggy Sunday night in New York hundreds of folks have thronged to a converted church, now a club, called Limelight. In conjunction with the New Music Seminar, Guitar World is sponsoring a concert featuring Satriani.