I went to post a comment on Splunk Answers using my Chrome web browser and the behavior was most peculiar. I clicked 'Add comment' and got the comment box, then typed-in my comment and clicked the blue Submit button. The button changed to a lighter blue but then nothing happened. After a while I re-loaded the page and there was no comment. Tried it again. Same thing. Then I fired-up Firefox and was able to add a comment with no problem. In both browsers I was logged-in. I'm using Version 40.0.2214.91 m. Oh, and by the way, I asked this question using Chrome.
I am using Chrome Version 40.0.2214.94 (64-bit) on a Mac, no problems. I've been using Chrome on this site since it switched platforms (recently) with no problems... Not saying that you didn't nave problems, of course!