http://www.usatoday.com/news/washington/2006-05-10-nsa_x.htm
At least at Sprint PCS, this type of data delivery is fairly easy (technologically) to provide. Instead of specialized pen register or trap and trace setups, now all is needed is a SQL query and a data tape. Since ~2000, Sprint PCS collects all CDRs at a central location where they are inserted into a database running on an SP2 cluster. Even for just Sprint PCS, this is a huge setup (multi-terrabyte) just to process 15 days worth of data. When I worked on the system, the plan had been to store anything over that out to 60 days in a tape library and then overwrite it. If the NSA is processing CDRs from multiple telecoms, they have an enormous cluster dedicated to the task--- all paid for by the taxpayers.
The type of information is essentially what number called what number when and for how long. Personal information is not part of the CDR but can be looked up from other sources. With this kind of information, NSA can compile data on social circles, political and religious affiliations, etc. They can also use it to dig up dirt on people or government officials and blackmail them (affairs, afiliations they do not want public, etc.). How this collosally expensiv undertaking helps them fight terrorism is questionable. The telecoms who participated said that they were working with the NSA to 'protect American citizens'. Who, I wonder, protects us from the NSA? Obviously not the department of justice: when the two DOJ attorneys tried to investigate another NSA domestic surveilance program, they were told the information was classified and that the DOJ did not need to know.
