It's easily scratched. I managed to get a scratch on mine after 24 hours of usage. I wansn;t doing anything extreme about it. If I compare it to my naked Samsung Galaxy S screen, it's way behind.
I am using my phone for past 6 months, without any sort of protection and it doesn't have a scratch on it's Gorilla Glass.
I was really dissapointed that I can't say the same for my new iPad 2. I gotta buy some smart cover or screen protector ;/