I disagree with most of you here!!!
Googoosh had great memorable songs back in the 70s and more or less shit now, she had a good voice when she was young and naturally at 70 she sings better than most 70 year old women but what distinguishes her from all our other singers, is her vast international fame.
Other Persian speaking nationalities may like some of our other singers and attend their concerts but in no other concert, non-Iranians (Afghans/Tajiks/non-iranian Kurds/etc.) gather in such vast numbers as they do in Googoosh's.
Still to this day, she's the one setting the norms of this industry/breaking records, etc.
I for one am very very proud that we have such an internationally acclaimed star like her and I hope she lives and stays with us for a very long time!
After her, we have no one to take her place in the above mentioned department.