I can't speak for everyone, but if you have positive feedback for a startup, write a nice blog post and send them a link. If you have negative feedback, send th

I can't speak for everyone, but if you have positive feedback for a startup, write a nice blog post and send them a link. If you have negative feedback, send them an email about it. If their response of lack of response is particularly noteworthy (if they are rude, or they fix the issues very quickly) it might warrant a blog post. Personally, I don't blog, but I enjoy sending emails to startups whose services I use, with my first impressions, what I like, and what could be improved. I realize that this isn't a novel concept, but it's interesting to chat with the founders themselves, and sometimes it seems like they are really lacking in feedback in certain areas.