too hard to understand, even with the recipes. I wish the m_r interface would be more perly, but it is constrained by being Apache conf items, after all :(
(this one's hard to explain, I'll try anyway...) wrong focus: m_r does "just" rewriting; I described but one part of content negotiation. Right now I'm serving all my PNG images with linking to just their basename. I'm in the progress of adding SVG versions, and an advanced UA will prefer the SVG during negotiation (in case both are available and the type has a higher accept value, well you know how it works). m_r does not offer that seamless semantic meaningful switchover in any easily discernable way.
Well, that's a long--and often religious--discussion. I meant more for simple .cgi or .pl Installations. Another problem is that most software has to be either designed that way (e.g. point at foo/bar, not at foo/bar.pl) or the output has to be parsed.
Personally, I prefer no extensions for URIs with html content themselves, but let them stay for images, stylesheets and so on.
Ordinary morality is for ordinary people. -- Aleister Crowley