I have no clue. Seriously, the users who talk to me are maybe 0.1% of the total FreeBSD/EC2 user base.
I would love to know who is using FreeBSD in EC2.
I can tell you some financial services I have worked for do use FreeBSD on EC2 as well as on the metal in data centers to do millions of transactions a month.
I like the OS, thanks for your work.
Does netflix only use it on their edge boxes?
Yes, their CDN is FreeBSD but last I heard all of their cloud operations are Linux.