Rails Bigwig Rails on Rails Community
I'm not making any argument against Mongrel technically. I was trying to soft play it, but here's the hard version: Do you really want a piece of code in your software stack from a guy that is a loose cannon like that? Now that the cannon has gone off, do you want to be pulling updates from this guy's svn server into your software stack? A project is both about the people and the code. This is why, contrary to this guy's opinion, Rails is good (and more so on the people than the code, actually).
I can longer consider using Mongrel unless there is independent review and/or this guy's committer access is revoked. Permanently. Since the only person who can revoke it is him, for Mongrel to be useful, someone needs to fork it right now from a 'last known good' version, into an independently controlled repository.
Failing that, my message to other people using Rails is that there is alternatives to Mongrel, so don't let not wanting to use Mongrel dissuade you using Rails.