I'm currently far down the database rabbit-hole and have to ask: What's so great about Cassandra that you can't get with CouchDB or other AP (yeah, I know...) databases?
Solid ingestion story. Very very good write throughout. Linear scaling. Easy expansion / contraction. Complete flexibility in consistency vs availability tradeoff.
And most importantly:
It actually works at scale. Huge scale. Thousand node cluster and hundreds of thousands of instances scales.
Because a good chunk of the active maintainers actually run this shit in prod.
