By an overwhelming margin, investors chose London as the world’s top commercial property market, according to an annual survey by Washington D.C.-based Association of Foreign Investors in Real Estate.

London moved past Washington D.C. and New York, with Paris and Tokyo rounding out the top five. In the 2009 survey, London was second, in a virtual dead heat with New York and Washington, but this year respondents chose London by a wide gap, the association reports.

Fifty-one percent identified the U.S. as the best opportunity for capital appreciation, compared to 37 percent in 2008 and 26 percent in 2007. Two-thirds of respondents said they planned to increase their U.S. investments in 2010.

The annual survey reflects the responses of 200 AFIRE members, who control more than $842 billion in real estate.

Analysts agree that 2010 won’t be a banner year for residential property in London. At the very least, there is consensus that the market is unlikely to return to the heady days of cash-crazed Russians, million-pound designer lofts and double-digit price growth.

But analysts are far apart in their actual predictions for the market, suggesting that no one is absolutely sure what the hell is going to happen.

U.K. estate agent Savills this week issued what one London paper termed a “groveling apology” as part of a settlement with an ex-client, who charged the agency with defrauding him of more than £7 million (about $11.7 million.)

The latest forecast prepared by the Centre for Economics and Business Research for Chesterton Humberts predicts growth in U.K. prices in the next year, disputing more pessimistic recent reports.

Although there might be a more than touch of boosterism in Chesterton Humbert’s position--the release is scarce on details and specific forecasts—the consultancy cites several reasons for optimism. For one, interest rates should remain low, while lending loosens up and mortgages become more available. Plus, there will likely be a shortage of supply, especially in London, the firm argues.