A Google Groups thread discusses the ramifications content warning pages have on search engine visibility. See, if your blog has questionable content, the Google Blogger platform will put up a warning page. However, the problem is that this page itself impacts visibility in the search engines substantially. The problem is described here:
The content warning page uses a DIV-tag/javascript for the relevant button. There is no regular link from the Content Warning page to the blog itself.Even if Blogger is a part of Google, no one has apparently told the Google spiders how to find away around this javascript.
So what happens now? JohnMu acknowledged that Google is aware of the issue, but there's no fix for it just yet.
Forum discussion continues at Google Groups (#1) and Google Groups (#2).