There is no easy answer for how much is really captured.
Real-time tracking is almost impossible.
The wireless telco (verizon, att, etc) will have some retention period on the raw tower data-
and maybe roll it up in batch- but it won't be visible right away and
it may involve resources/cost to share with other agencies.
My guess is that size of the tower data is very small - so a lot can be
saved cheaply and stored for long periods of time.
The raw voice data is probably sampled at the backend data center with
different crew of analysts.
So it probably is possible to line all this up - within a certain window-
but there would have to be a good reason for the telco to do the work.
I have seen some articles about "dark" towers that could potentially do
much more - but their primary interest is probably not info on SPs-
but they probably get a kick out of listening to the conversations.
Slinky/Popeye
The following is my opinion on phone mapping just from looking at some recorded map examples - if anyone here has technical expertise in this area please correct/add/ verify.
If you look at a typical recorded map (if the one I saw was typical) you will see that the data are not recorded continuously, but by (perhaps at least and maybe with some other criteria thrown in) some time period . The map data I saw consists of points connected by straight lines and not continuously unless the phone being tracked went via helicopter or driving through buildings to get from one point to another. This time period may be sufficient to identify you being at a certain place and time if you were there for greater than the sample period, e.g., you spent some time dumping a body along Ocean parkway or were at a motel for a period of time to see "a friend".
Whether or not there is sufficient data storage in NSA's "data farm(s)" to continuously record every cell phone and then index the data in order to find whether or not some discrimination criteria were met, e.g., find all phones that were at location X between time 12 pm and 12:02pm on June 2, 2014, is the big question - it is an astronomical amount of data and monumental task. It is another story to target a particular phone and record its location data or target a particular location and record the phones that were tracked by a tower and then target those phone's GPS location data.
NSA has powerful tools but keep in mind it took 10 years to find and kill Bin Laden (a 6"6" tall Arab on dialysis ).