Yes I've noticed this too... On one post I saw today, there were at least 10 well written lengthy robot-generated spam comments highlighting the virtues of understanding how to use the steemit system properly. Man that was so much better than the traditional "good post" spam of the past. I was thinking how awesome it is now that the spammers are rich articulate people now instead of poor 2-word users. This is really a major improvement, so I'm super shocked that the subscriber numbers haven't shot through the roof yet. ;)