Out of habit - most blog comment systems I know allow for it - I just used a couple HTML tags in a comment, to no good effect. I think that changing the little label I discovered afterwards on the profile page from "help" to "formating options" could help prevent such mishaps, since "help = formating options" in this case. Also, making the gray of said label a tad darker would make it easier to see - it's a bit "hidden in plain sight" the way it's now, to the right of everything else on the page.