progress bars om Linux GUI
Progress feedback is really important, especially where cloud storage is involved. I don't suppose it needs to be terribly precise. I've seen a bunch of backup programs with more or less the same problem: people try to parse out precise information about how far along the backup is from whatever is there, no matter how imprecise it might be. Human nature, I guess. They need to know what they need to know. Thing is, I haven't seen anybody do a great job of making clear the precision or lack of it in the available information. So, viewed in that light, you've got a clear playing field.