Britain and China are just signing up some mutual trade agreements, a lot depends on how much debt foreign parties are prepared to buy. It's doubtful the UK will join the euro, alhtough Mandelson has been talking to the Europeans about it, so the idea that has happened without Browns knowledge is piffel IMO. Brown engaged Mandelson.

Euro currency membership won't happen

a] we don't meet Brussels economic requirements

b] PIIG countries, ie Portugal, Italy, Ireland, Greece, think the euro is preventing them from managing their economies effectively. Also Brussels may have caught a cold with the USD squeeze. It's conceivable the life of the euro may be strictly limited.