Since sometime on the 15th September, all the email notifications for comments I've received from Blogger have not included the blog post title in the subject of the email.

Also, the content seems a little messed up. The multipart MIME encoded email just displays as plain text without it being decoded / interpreted / parsed. (I can't figure out what they're doing wrong, but it looks like they might have added a line break to the subject which could be breaking it.)

Is anyone else seeing this?

Yes, I do. But some of the comments look well. Google is aware of this problem:
http://knownissues.blogspot.com/2007/09/comment-moderation-email-appears-broken.html