Karl Miller:
>Is there any composer today who, at the age of 40 or so, is considered
>a master, with each new work of his or hers being eagerly awaited by the
>concert going public?
Not sure how eagerly, but perhaps:
John Adams
Jennifer Higdon
Theofanides
Poul Ruders, at least in Europe
Ades (?) in some quarters; I can't stand his stuff myself
Jim Tobin