I've given at least three talented writers input via the Internet. And I enjoy doing it, although it can be tricky to give constructive criticism without seeing the author's face. I hate the thought that I might hurt someone's feelings. This is why I love my writing group. We meet every other Tuesday, usually 7 - 10 people, and we read our work. Then each person gives his/her feedback. It's a wonderful forum because we can see each other and gauge reactions. Also, it's great to get feedback from multiple points of view. For example, if everyone hates your phrase "her eyes twinkled like cat litter," then you know it probably needs revision. But if only 3 or 4 people hate it, while the others think it perfectly captures the odd beauty of cat litter, then you can make your own mind up. In addition, writer's groups help you understand what is clear and what isn't. You know, as an author, all the secret ins and outs and motivations of your characters and your plot. And when you read your own story, it's all perfectly clear. Yet a group can clue you in to when they were confused. This is a great advantage, especially in editing and rewriting.
I struggled for months to find good feedback. Then I went to Meetup.com and searched for writer's groups. I found over 50 in the Triangle area. If you are a writer and you don't have at least 1 reliable critic, preferably 2, then get thee to a writer's group!