I am too!
Since Kumar brought it up, I'm going to put up some tips for fellow readers.
Please don't click on any links in comments/posts unless you know the poster. That's the first safety rule.
Moreover, do not click on their blog pages. When you hover the mouse over their blog pages, it might read something genuine like my-cool-blog.blogspot.com but in reality it redirects to their spam sites, so don't be tempted to click on it.
Other than that, here's what you can do to stop them:
(1) Go to Settings -> Comments -> Show word verification for comments? Set it to Yes. This way if it is a machine doing it, it will stop right there.
(2) If the comments don't stop after you put in the word verification, then on that same page, Enable comment moderation? Set it to Yes.
Three spammers I have spotted are: Guhn, Grogal, and JoJosho. Their profiles are going to be reported to whom it may concern. Cheers!