It's not that Google thinks comments are a bad thing, it's that if your site gets an average of 50 comments per article you need to KEEP ON GETTING 50 comments per article just to maintain rankings benefits, imo of course.
This all changed last Wednesday. From what I see, unless your comments are 400 characters long and in perfect English, they will hurt your rankings. I was about to start on a project to move all my comments to being displayed through AJAX so Google couldn't crawl them. This is a better solution.