I uploaded two videos, one for GNU Radio and the other for Windows - the one you linked to is the Windows one, the first one in my OP is the GNU Radio one. The accompanying links to the GNU Radio Source block code, so you can use it as a capture device in GNU Radio, and the second is the Windows installer so you can use it out-of-the-box on Windows.

Hi folks,

If you want to start using the USB stick for SDR, please check out the follow options:

GNU Radio Source block 'rtl_source_c' in 'gr-baz' module: http://wiki.spench.net/wiki/gr-baz#rtl_source_c
Demo video: http://www.youtube.com/watch?v=FUQd9HOVTk8

ExtIO plugin for Winrad/HDSDR/WRplus: http://wiki.spench.net/wiki/USRP_Interfaces (grab the beta)
Demo video/install guide: http://www.youtube.com/watch?v=Z0hEquzLsWU

Let me know how you go!

Shameless self-promotion ahead...
This is more a suggestion to help with mapping received signal strength (RSSI), rather than data network latency and bandwidth (you can argue that those data network metrics rely heavily upon your RSSI!):
Grab an old Nokia, use gammu to enable Network Monitor mode, fire up a GPS and display the combined information streams on a map. I did exactly that as an experiment using a Nokia 3310 and a Navman GPS receiver. Interesting to then correlate the signal peaks to the actual base station locations.

The main caveat is that the old Nokias in question only do (I believe) dual-band 2G GSM at best, so you won't actually be able to measure 3G W-CDMA statistics as if you were connected with a 3G data device. I would offer, however, that 3G RSSI might be related to that of 2G as many of the base stations handle both services (ignoring differences in signal propagation characteristics). A starting point at least...