I get a lot of spam comments on this blog - Askimet protects me from around 2000 a month. (The most recent was from 'Luxury Car Makers' who attempted to leave a comment on a post I wrote ages ago entitled 'Why the BL e-books announcement is really important' and which consisted just of 'I hate Lady Gaga'. #fail) But a new one on me has just occurred, twice in two days, so here's a warning in case they try it on you.
The comment consists of effusive praise, stuff about how well written the post is and how astute it was etc, written in decent English. There are no links in the comment at all and - this is where it differs to previous spam I've had - no link attached the name, either. Most spam comments either try and get you to go to websites by clicking on a link within their comment or by clicking on their name - in the same way that if I commented on your blog, your readers would be able to click 'thewikiman' next to my comment and get back to this site. So these new comments have no such link - hence Askimet not flagging them as Spam, and them making their way through to my comment approval queue.
On this blog, if you've commented before (and enter your details the same way again) your comment is automatically approved, but if you're a first-time commenter I have to approve it. So the only agenda I can think of for this new type of spam is to flatter the user into approving the first one, and THEN commenting about a gazillion more times with proper spam, full of links to dodge stuff, before the blog author can do anything to screen them.
So, just a quick warning in case it happens to you - make sure you don't approve that first flattering comment!