The 12 countries with the largest Jewish populations (data as of 1/1/2010):

Israel – 5,703,700*

United States – 5,275,000

France – 483,500

Canada – 375,000

United Kingdom – 292,000

Russian Federation – 205,000

Argentina – 205,000

Germany – 119,000

Australia – 107,500

Brazil – 95,600

Ukraine – 71,500

South Africa – 70,800

Total - 13,003,600

*includes Jewish residents in East Jerusalem, the West Bank and the Golan Heights; does not include over 312,000 immigrants admitted to the country within the framework of the Law of Return who were not recorded as Jews in the Population Register

Here are some comments on the findings from DellaPergola:

Beyond the many and arguable problems related to Jewish population definitions, and beyond data availability and accuracy, it is important to recognize that powerful and consistent trends constantly shape and reshape the demographic profile of world Jewry. It is important that we read current data in historical and comparative context. The recent momentum of Jewish population change in the United States- at best tending to zero growth – contrasts with that of Israel- characterized by significant natural increase. While the transition of Israel to the largest Jewish population in the world is grounded on solid empirical foundations, the United States remains a very large, culturally and socioeconomically powerful, creative, resilient, and influential center of Jewish life. The aggregate weight of other Jewish communities globally – aside from their continuing cultural relevance – is gradually decreasing. In a Jewish world that has become demographically more bi-polar, the cultural and institutional projection and influence of the two major centers has become more significant in other geographical areas of Jewish presence.