Weirdly, Shazam have published a fairly thorough paper
on how their search algorithm works. While devoid of any actual code, it doesn't seem as though the blog in question has given away any trade secrets that aren't easily derived from this paper and other bodies of work online.
Of course, by threatening the guy Shazam & LDS have created their very own Streisand Effect; this is front page on
/., Digg, Reddit, YCombinator, etc., which means millions of people have now seen the "infringing" code, with many saving it or tweaking it. I'm certain someone will mirror it in a country that doesn't validate software patents as well. One also wonders if they're going to sue Google or demand they clear the cache.
As for me, I won't be using their software, and I will be contacting them to register my disgust, though it probably will make no difference in their attitude.