Thanks for sharing your experience. I had a similar pleasant experience at my N400 interview on April 9th at Denver field office. I haven't received my oath ceremony date yet though.
It's delayed for me, probably because of name change request and I had informed the officer during the interview that I'll be out of the country at the beginning of May. I'm hoping to soon get a ceremony date in June.
Could you share where your ceremony is at? A court in Denver or at the USCIS field office?