David Ayres (G4SXT) has reported a couple of errors in the detailed instructions for downloading and configuring the Raspberry Pi. It seems that the git site address changed just after publication and I omitted a sudo command ahead of one of the instructions. The corrected code is shown here:
Original: Type: git clone git://git.osmocom.org/rtl-sdr.git
New: Type: git clone http://cgit.osmocom.org/cgit/rtl-sdr/
There was also a typo in the original instructions as shown here:
Original: cmake ../ -DINSTALL_UDEV_RULES=ON
New: sudo cmake ../ -DINSTALL_UDEV_RULES=ON
Sorry if you were disappointed.