The Museum of Modern Art in New York has an extraordinarily diverse collection of masterpieces in every medium. On a recent visit, I headed straight for the photography in the Edward Steichen Galleries on the 3rd Floor; these show a rotating exhibit of MoMA gems from pioneers, such as Muybridge and Stieglitz, to the usual suspects such as Diane Arbus & Jeff Wall. I was very taken with several trademark street portraits by Harry Callahan (1912-1999), the first photographer to represent the U.S.A. at the Venice Biennale in 1977. Check out - http://www.moma.org/exhibitions/collection_galleries/photography.html
Edward Steichen himself (1879-1973) is the subject of a major, if partial, retrospective at the superb Kunsthaus in Zurich http://www.kunsthaus.ch/. Curated by William Ewing and Todd Brandow & entitled 'In High Fashion', the exhibit remains on show until the end of March & will subsequently travel to Madrid and Wolfsburg in Germany before reaching New York's ICP in January 2009 www.icp.org/.
A pivotal figure in the 20th century reappraisal of fashion photography, Steichen had already made his name as a painter and art photographer on both sides of the Atlantic when, in 1923, he became chief photographer for Condé Nast's influential Vogue & Vanity Fair magazines. His influence, both as a curator at MoMA and as the de facto creator of the prototype of the "super model" cannot be underestimated. My own highlights of the Zurich show included early portraits of British icons such as Winston Churchill & Noel Coward.