> However, I assume you'd have no objections to a layer built _on top 
> of_ Rails that accomplished those business domain problems? What if 
> there were made available as third-party "add-ons" or "plug-ins" to 
> Rails? That would leave the Rails framework itself light and generic, 
> with the option of adding specific functionality where the consumer 
> needed it.

Oh, no. That would be great stuff indeed! It's just that the thing 
called "Rails" is meant only to be infrastructure. Something called, oh 
let's say, "Trains" could be a cool project to put business domain 
solutions in.

But in general I'm fairly skeptical about generic business domain 
solutions. Hence my reservations over OpenACS, Zope, and the like.
--
David Heinemeier Hansson,
http://www.rubyonrails.org/  -- Web-application framework for Ruby
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http://macromates.com/       -- TextMate: Code and markup editor for OS 
X
http://www.basecamphq.com/   -- Web-based Project Management
http://www.loudthinking.com/ -- Broadcasting Brain
http://www.nextangle.com/    -- Development & Consulting Services