In NDPR, Kathleen Wright reviews
Dennis J. Schmidt's Between Word and Image: Heidegger, Klee, and Gadamer on Gesture and Genesis
The existence of a significant but unpublished work by Heidegger on Klee had long been rumored ever since Petzet reported that Heidegger spoke enthusiastically after attending an exhibition of eighty-eight paintings by Klee in Basle in 1956 about writing a second part on modern art for "The Origin of the Work of Art," an essay written in 1935. The examples that Heidegger had considered in 1935 were all works of art of the past, such as the Greek temples at Paestum and van Gogh's "A Pair of Peasant Shoes." In 1956, Heidegger confronted something new in the paintings by Klee. As he wrote to his friend, Petzet, in 1959, "Something which we all have not yet even glimpsed has come forward in [Klee's works]." However, Heidegger never published anything on Klee during his lifetime.
I saw the Klee exhibit at the Tate in December, and recommend it, if you're around.