Four things I love about it:

- It's "just" JSON and WebSockets. From a developer's perspective, it's incredibly easy to get started and build interesting things with it. (Like the early days of Twitter.) Which leads to...

- Nostr culture is tolerant of bots and other automated workflows. (Unlike current management of Twitter)

- Nostr culture is tolerant of search engines. (Unlike fediverse, or at least the Mastodon part, though I appreciate the reasons for that distinction.)

- Built-in micropayment infrastructure with "zaps" and Lightning Network integration enables a ton of interesting new startup idea possibilities.

One thing I don't like about Nostr, the social network. (Not Nostr, the protocol. Those two things are very easily conflated right now):

- Too many Bitcoin bros. (Although personally I don't mind Bitcoin, a thriving platform should have more than one thing to talk about.)

I should say though, that upon first look, I wish it was built on top of some already existing standard (like rss), as it could get a great headstart in terms of content already circulating in the network that way.