A look ahead

Even though museums have got themselves into the very strange position of no longer simply purveying culture, but competing with their fellow public institutions for box-office profits to fund increasingly elaborate bureaucracies, 2006 still looks set to furnish us with a richness and variety of visual fare. The National Gallery, disappointed in a poor turnout for Rubens, will hope to recoup on a trio of fine exhibitions, ending with the grand slam of Vel