The interoperability is the *killer app* feature in my mind. I am surprised that people don't highlight this aspect more often. Zaps are nice. Decentralization is good. FOSS is good. Uncensorability is nice. Resilience is good. V4V is good. P2P is good. But interoperability seems to me to be the most groundbreaking component and one of the most compelling reasons to join Nostr.