I'm looking at bzr baz-import, which is in its 18th hour of importing 40-something branches. But I wouldn't have known there were 40-something branches without using "baz branches | wc -l". The baz-import output shows me the progress of importing individual branches, but doesn't show me the most useful thing, the *overall* progress, so I know whether to go get a drink, or find something else to do, or cancel and restart using screen, or take a vacation.
As a minimal fix, I suggest "importing" be changed to "Importing branch x/y:", e.g. "Importing branch 31/52:".
A more thorough fix would be to print "Total time remaining: about xyz" underneath all the other output, e.g. "Time remaining: about 11 hours", constantly overwriting this with other output (so the listing of imported branches etc is recorded in scrollback, but the time estimate updates are not). This would be calculated as (time elapsed so far / branches imported so far) * branches remaining to import.
we now have nested progress bars so this can be done.