Now, lets take a look at a recent, relevant, and very concrete example: Google Maps support for GeoRSS. In order to deal with feeds produced by “average, relatively low-skill programmers” Google must deal with non well formed feeds, multiple incompatible formats (+ Atom, optionally including the declining but not quite gone Atom 0.3 variant), multiple ways to express GeoRSS data, and even deal with applications which don’t follow these specs either.
sam keeps adding tests to georss, nice!