I was surprised to see this is done with real hardware. I had expected VMs, or faking the user agent, or even reverse engineering the http requests and replaying them. Surely the economics is far better than buying 10s of thousands of phones. I guess theres a reason I haven't thought of.
I wonder why likes, stars, retweets and similar counters are not weighted by a reputation in a user visible way. For the user a tweet with 1000 botnet retweets looks exactly like a tweet with 1000 retweets by experts in a given subject.