Probably hysteria, but infrasonic emissions should be considered in the engineering. I have no clue what the infrasonic signatures are like for various wind turbines setups. I have lived near industrial infrasonic generators of other sources, and I have hated it before knowing anything about it.

Bottom line for me:

• wind powered electricity, good
• pollution of any kind, bad
• emissions are an engineering problem, not an intrinsic one (usually)