Connect to the DB and run "select * from pg_stat_activity" to see what specific query your other connection is running. Then find that in your file to see how far it has progressed.
I hope you profiled your queries to make sure they run fast before you started. :)
I have a fairly large table (4.3 billion rows) that I am running an update script on (a bit over 127 thousand individual update queries). I am using the gui. It has been running for about 24 hours now. Is there any good way to gauge progress (as in, how many of the individual update queries have finished)?