Alex Ross in The New Yorker:
Beware of conductors who compose. They often produce what is known in the business as Kapellmeistermusik, or conductor’s music, in which interesting orchestration goes in search of original themes. Wilhelm Furtwängler wrote endless quasi-Brucknerian disquisitions, including a seventy-minute-long, brain-emptying Piano Quintet. Lorin Maazel, whose opera “1984” premières next month at Covent Garden, has some high-gloss Kapellmeistermusik to his credit. Michael Tilson Thomas recently presented a cycle of Emily Dickinson settings with the San Francisco Symphony, and although he doesn’t yet have a distinctive voice he has at least found an elegant and uncluttered style. Leif Segerstam, a Finnish conductor, has generated a hundred and twenty-two symphonies and counting. I’d like to report on them, but life is only so long.
Esa-Pekka Salonen is a different case.