While the blog is mostly down, here is a summary of the problems pointed out by the author:

1. View index updates - "Every write sets up a trap for the first reader to come along after the write"

2. Append-only database file - "Create(s) a huge operational headache", disk utilization, compaction, etc

CouchDB has always been a poor choice for write-heavy applications. Sounds to me like a case of selecting the wrong tool for the job.

Though I'm a big CouchDB fan myself, I wonder why the author didn't go with a traditional RDBMS for this application.