Al is correct; if only a certain section of your site has been
affected by malware (such as the /blog subfolder), you'll need to add
that section specifically to your Webmaster Tools account in order to
see the malware review notice. A great way to figure out which
section(s) have been affected is to do a site: search and see which
URLs have the malware label in search results.
Al, I agree that it would be nice to bubble this up to the top level
of the site (so that you can look at the Overview page for example.com
and see that there's malware on example.com/blog), and I've passed
your feedback along to our team.