And the plot thickens:
in at least one instance, someone using an international cellphone was thought to be outside the United States when in fact both people in the conversation were in the country. Officials, who spoke on condition of anonymity because the program remains classified, would not discuss the number of accidental intercepts, but the total is thought to represent a very small fraction of the total number of wiretaps that Mr. Bush has authorized without getting warrants. In all, officials say the program has been used to eavesdrop on as many as 500 people at any one time, with the total number of people reaching perhaps into the thousands in the last three years.
That doesn't sound like very substantial data mining to me. Maybe the Echelon theories are off base and this is a more targeted, focused program. For now, the best hypothesis I've seen comes from DefenseTech:
Another [signal intelligence expert], who's generally very pro-Administration, emphasized that the operation at least started with people that had Al-Qaeda connections -- with some mass-spying master list...But this call chain could very well have grown out of control, the source admits. Suddenly, people ten and twelve degrees of separation away from Osama may have been targeted.
In any case, as I said in the post below, we've really no idea what's going on here. Too much of the evidence contradicts, or fits best in opposed theories. Or, scaling up, we may have some grand unified spy program operating that combines elements (or all) of every hypothesis yet discussed. Man are those Senate hearings gonna be interesting...