Amazon continuously send me emails prompting me to review items. I get that reviews are useful and there's a sort of tragedy of the commons at risk here if users don't leave reviews, but honestly I also don't feel like working pro bono for a megacorp.
@srs yes, I agree.
But ideally we could instead try to push third party arrangements for reviews -- perhaps distributed/user owned/[[agora]] like. See Twitter for discussion with @karlicoss