[1] Others executed for criticism ("poetry" about muhammad as it's generally called in the hadith) include "Abu Afak", "Al Nadr ibn al-Harith", "Uqba bin Abu Muayt", "Ka'b ibn al-Ashraf", "Abu Rafi' ibn Abi Al-Huqaiq", "Fartana" and I doubt this is anywhere near the full list.
Note that this was most definitely NOT common practice during those times. You should read some of the texts that survive from Roman fora in the same area. Let me tell you Romans are not afraid -at all- of calling the head of the army a coward, and comparing them to dog entrails (I assume that's not a compliment). Same sort of things are regularly said about the governors and so on. And in at least one instance that did not even lead