It looks like he ran Sam Soffes' json-benchmark: https://github.com/samsoffes/json-benchmarks
That being said here are the results I got on my iPhone 4 (compiled with -Os) Reading: http://yfrog.com/khul0wsj Writing: http://yfrog.com/h0nqgzej
That being said here are the results I got on my iPhone 4 (compiled with -Os) Reading: http://yfrog.com/khul0wsj Writing: http://yfrog.com/h0nqgzej