A fascinating document has been published by Alexei Krindatch of SCOBA. It looks at actual numbers of Christians affiliated with Orthodox Churches in the U.S.
The .pdf report may be perused here.
One would wish that somehow Mr. Krindatch had investigated how many of these Christians are involved with parishes and monasteries that offer Western rite services, as distinct from Eastern rite parishes and monasteries.
It is also apparent that the "grand total" of just over a million Orthodox Christians in the U.S. who are affiliated somehow with an Orthodox church, is an over-estimate in that it includes many Christians whose belief is different than ours (Oriental Christians, whose hierarchy adheres to Monothelite heresy). On the other hand, because the total excludes individual Orthodox Christians isolated from any parish, and many unrecognised jurisdictions (oddly, two and only two were included), it is, to that extent, an under-estimate of the true total of all believers.
This represents a significant advance in accuracy of data, since previous estimates relied directly on totals provided by various jurisdictions. It had come to light previously that these totals were not supported by available data, and now this more-accurate census has been undertaken.
It is good to see that between 2000 and 2010, the Russian Church Abroad experienced an 8% rate of growth as to the number of parishes and monastic communities. Certainly, there has been substantial growth in the Western rite of the Russian Church Abroad, not to mention the foundation of new parishes and missions. The Church Abroad prish in Austin (Holy Protection) appeared in 2001, and has grown since.