Logging is quite simple, actually. You just need to check the checkbox to enable it in Upload dialog, select a common directory to store the upload logs, and there you go (if on Mac, I suggest iCloud documents or another cloud accessible folder for easy checking on the go away from your main computer). Log files are simple txt files in year month date format in the filename, and if you are using Mac, you can just do a spotlight search for the suspected filename of the uploaded photo, and if the folder the logs are in is indexed by spotlight, it will pop up. Being simple txt log files, they are very small, two years of logs for me takes just under two megabytes...
Being just super simple small text files, I generally leave the option on all the time, comes handy if I need to check with the client whether the fault they can't see the uploaded photos is on my side or their media management server side (usually the latter
).
Added bonus of it is if you upload same photos to multiple clients - you can still get all the info from the logs, when the green box would tell you it uploaded just for the latest upload.
For me, simplicity is the key here - until PM gets Cataloging, any saving of what files where uploaded to which ftp server and when would need either a central catalogue of sorts or saving the info in the folder itself (not optimal for the long run). When PM gets cataloging finally, I guess it would be a nice feature to possibly integrate upload logs into the catalogue, especially if you could combine them somehow with job tracking and Job/Client screen/variables (possibly by matching the ftp server). Until then, simple log files, saved in user defined central location, readable by any text viewer and operating system are the simplest, thus the best for me. Sure, it would be nice for the indicators to be persistent, but if you take into account you can upload one photo to multiple locations, and where could the persistent info be stored, the current state just works for me