Fairy-Wing Throwdown

or

JSON v XML

or

How much slower, exactly, is XML in the real world?

Backstory is dramatized at http://blog.flavorjon.es/2011/03/json-vs-xml-fairy-wing-throwdown.html

TL;DR

1. Is XML parsing more than an order of magnitude (i.e., 10x) slower than JSON parsing in real world situations?
2. Both @pauldix and @flavorjones think XML parsing is slower than than JSON parsing.
3. @pauldix says XML parsing is more than an order of magnitude slower than JSON parsing.
4. @flavorjones says XML parsing is less than an order of magnitude slower than JSON parsing.
5. The loser must wear @flavorjones's daughter's dress-up fairy wings on stage throughout @pauldix's RailsConf 2011 presentation.
6. Benchmarks must be performed by close of business Friday, April 1. (No, this is not an April Fool's joke.)

Tentative Conditions

1. Benchmarks must be performed on Ruby 1.8.7 with any standard compiled extensions / gems.
2. Objective is a specific data structure actually used by these Gentlemen at their place of business, Benchmark Solutions (see data.json).
3. Code must take a string (JSON or XML), and return an inflated Ruby data structure exactly matching the objective.
4. Timing should encompass only in-memory operations (not IO).
5. @jvshahid will be the arbiter of whether the implementations violate the spirit of "real worldiness".