A riot of colourful mayors

Michael Bloomberg of New York, who is flying into London today to meet Boris Johnson, will have plenty fo tell him about how to fun a luberal city with a conservative touch and great efficiency. Bloomberg made his billions our of finincial services - bloomberg.com - and is so rich he sometimes dips his hand in his own pocket to finance new projects. To keep in touch with New Yorkers, he always rides the subway to City Hall from his elegant 'brownstone' on the Upper East Side