As a result, the "Next Blog" link in the Navbar would, quite likely, load on your computer a blog which you wouldn't want your kids to view. This was the result of what I believe to be a well organised criminal, hacking campaign which used BlogSpot.Com to host blogs that led, intentionally, to hacking content designed to make your computer part of another botnet.
There was a side effect to the hacking activity. The front end to that activity used porn - in various forms - to entice the reader to click into the blogs containing the hacking activity. And, with the thousands of blogs that were part of the hacking activity, came the smaller operators, who innocently provided adult content, though not with illegal activity intended. Personal blogs, that contain porn.
With the illegal blogs removed, at least temporarily, came more traffic to the genuine personal blogs, like yours and mine.
With more traffic using "Next Blog", as people learned that "Next Blog" was less likely to land them on blogs that offended them, came increased scrutiny of the "porn" blogs that remained - the personal blogs that contain porn.
So Blogger provides another way of policing our personal blogs, and prevents casual access to blogs that may offend. In Settings - Other, we see "Adult Content?". This switch allows the owner of a personal blog containing porn (or other possibly offensive material) to proactively prevent casual access to his (her) personal blog.
If Yes is selected, viewers of your blog will see a warning message and will be asked to confirm that they want to proceed to your blog.
But that extra screen is a problem - it reduces both personal readership, and automated readership. Along with preventing casual access by humans, comes the side effect of blocking access by search engine spiders and other automated processes.
- The extra click on "Yes, Proceed" is not something that all automated processes will normally follow. Less indexing of personal porn blogs = less traffic to personal porn blogs = eventually, less personal porn blogs.
- Some spiders will pick up the content of the warning, and display its words in the SERP entries that list your blog. Incorrect indexing of personal porn blogs = less traffic to personal porn blogs = eventually, less personal porn blogs.
The reduction in personal porn blogs will have more effect.
- More people will use "Next Blog", as they learn that it's safe to use.
- More users of "Next Blog" will provide more people to object to any porn content.
- If and when the criminal hacking porn blog operators return to publishing on BlogSpot, increased scrutiny of objectionable content will make it easier to spot their activity. They won't become as blatantly common as last time.
- Increased attention to reports of objectionable content will make it harder for the criminal hacking porn operators to remain in BlogSpot, period.