Good comments are just as important as good posts, in fact probably more so. Like @pinay mentions she makes more on a good comment than on a good post. I haven't that much success on either, but if it weren't for interacting through commenting I would be making pennies versus nickels.

I think the most important with commenting is making sure that your comment contributes/reflects the post. I wish I could find this one comment I saw. It was something to the effect of the poster saying 'Peanut butter' on a post such as this. Completely inappropriate.

Thank you @biyanoor :) For sharing some great tips on commenting.