Spotted in inessential.com

I’ve been getting a ton of random-letter comment spam lately. Does anybody know what the purpose of this is? Or have any theories? The comments are weird because they’re apparently useless. No links, no words. They’re not selling anything or trying to get a better Google rank. They’re Zen comments. What’s the point of them?

I'm seeing that too, but mostly on the Wiki. The only guess I have - and it's a guess - is that someone is testing a new spambot?