there should be a percent progress in /save_url/check_job_status , otherwise it's useless for uploading big files . User won't know when there files will be uploaded . But there are some sites which showing percentage of upload , don't know if they are showing fake progress bar .
I would assume this isn't done to discourage large uploads. I second the request, I'm uploading a 130GB file on 30Mbs only and I want to know if I should pause it for the day when I work or if it will be hogging my troughput only for 1-2 hours more.
I also often upload 2-4GB images to publishers and on deadlines it's annoying for them not to know exactly how long my upload will take. Even a few minutes is valuable time at the deadline.