Here's the rant I posted to Facebook when someone posted about this a couple of years ago. The site that was on Facebook 404s, including the Wayback Machine, so I can't share all the craziness:

The simplest argument against this is the casual way your typical garage bands tune. Not everyone is busting out the tuners and dialing up 440 Hz, when the guitar player figures out they're out of tune with the bass they just tune up to wherever they're at. With strings stretçhing, drop D tuning, and tuning down a half step, most bands would have hit the 'magic' 432 Hz every other practice and would have stayed there if it had any special properties. And this isn't just me and my buddies in the garage but musicians of nearly every style, genre, and background around the world. We'd revolt if we found our magic 432 Hz and then some clown brought a keyboard in that was at 440 Hz. This simply doesn't happen.

The 'cymatics' demonstrations are great, even the professors I work for get excited about how these demonstrate standing waves in materials. Unfortunately for the 432 Hz people the wave patterns depend on the vibrating materials. I make music out of vibrating strings, resonating wood and digital beeps and boops instead of square plates of metal (nothing against square plates of metal, I'd use those too). So maybe they should start by making pretty pictures of sand on top of a guitar to have a point with the cymatics. Also, the tuner they keep showing for the notes in their video shows their frequencies sharp or flat. They should at least get their notes right. They're also using a modulated tone with harmonics which introduces all kinds of questions about whether they're trying to prove a point or just make cool patterns with the sand. But really, who cares if it sounds good, right? Seriously, if you like your music 'detuned' to 432, go for it.

I've got a theory that altering familiar music is a great way to get us in different moods. We like remixes, right? So a 432 Hz retune might be just the thing to mellow out to. Likewise, a 448 Hz retune might be just the kick in the ass I need in the morning to get going. So retune all you like.

I do have a technical quibble with the suggested method in Audacity, the resample will do bad things to the high end of the music, all those harmonics and partials and stuff (of course, some feel all that is lost in digital music anyway so YMMV). The Audacity wiki talks about better ways to do frequency shifts. I definitely wouldn't do this to anything that has been digitally compressed at any point, your mp3 folders and itunes collection will lose even more when you start pitch shifting them. Rip the original CDs and mess with the .wav files or get the FLAC files if you're serious about retuning your music collection.

The real way to test their idea would be to blind test a bunch of music you've never heard before, some that has been pitch shifted to a variety of frequencies including 432 Hz and some that is unaltered. Score the music and your emotions after each song and see if there is a pattern to the pitch shifting. Now do this to a bunch of people and see if there are patterns in cultures, age groups, musical preferences, etc.