Thanks for the assist folks. Based on what you all said I tracked down that update-manager had offered, and I permited, an update to libgphoto2 which on installation updated /etc/udev/rules.d/45-libgphoto2.rules (the only file in that directory which has changed recently). The beginning of that file looks like:
# udev rules file for libgphoto2 devices (udev >= 0.98)
#
SUBSYSTEM!="usb*", GOTO="libgphoto2_rules_end"
ACTION!="add", GOTO="libgphoto2_rules_end"
ATTRS{idVendor}=="0553", ATTRS{idProduct}=="0202", MODE="0660", GROUP="plugdev"
ATTRS{idVendor}=="06bd", ATTRS{idProduct}=="0403", MODE="0660", GROUP="plugdev"
ATTRS{idVendor}=="06bd", ATTRS{idProduct}=="0404", MODE="0660", GROUP="plugdev"
ATTRS{idVendor}=="04fc", ATTRS{idProduct}=="504b", MODE="0660", GROUP="plugdev"
and goes on with lots of those lines. I seem to recall being required to restart the system because of something in the group of updates. Perhaps it was this update since this file might need to be reread by a driver module loaded to (or in) the kernel. As I initially reported I saw the lines on startup (restart?) because I have the quiet splash turned off. After seeing them is why I checked the log.
Anyway, my strong suspicion now is that the log lines I was questioning are either generic reports of adding unspecified products to the list, or error reports of products not being added because the vendor (and therefore product) were not recognized (poor reporting IMHO). I hope the former, but fear the latter (solely based on the messages appearing in syslog).
It would be good to know how to find out which is the case, but I am no longer worried about it.
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