Here's a Christmas treat from the Dulwich Picture Gallery in London: Norman Rockwell's America, which opened today and runs until 27 March 2011. This is the first exhibition in the UK of original works by the "best-known and most beloved American artist of the 20th century." What a brilliant way for the gallery to begin celebrating its 200th anniversary in 2011, with the work of a real artist, not those Mickey-takers who show rubbish in Tate Passé. This is a major retrospective of Rockwell's career, including all 323 Saturday Evening Post covers created between 1916 and 1963 plus his illustrations for advertisements, magazines and books. It's a must.