After some vendor delay, we have licensed and enabled the Akismet comment spam filter for all blogs. Comments posted in response to articles on your blog will automatically be checked for spammy content so that you will be pestered less often for comment moderation. If a spam comment does get through, simply mark it as such and Akismet will learn from its mistakes.
For an overview of comment spam protection, take a look at the Comment Moderation article in the WordPress Codex. The many settings in WordPress that can help limit this problem can be found in your admin dashboard under Settings → Discussion.