According to Hometrack, London prices have risen 1.2% in the last four weeks, that's twice the national average rate. Hometrack's Richard Donnell points out that this tale of two markets might be flattering the overall UK picture. He says it's not set to last, though, and points to the World Cup, possible interest rate rises and the current stock market volatility as all reasons why some of the wind may leave the housing market's sails this summer.