What is "goo.gl", and why are they surfing my blog?and
When I clicked on a log entry for "bit.ly", I got linked to a porn site. I don't want my blog associated with porn!
This misuse of our blogs is not new - spammers have been doing this for years, to trick us into surfing to their websites.
Originally, blog owners who scan their access logs, such as Stats "Traffic Sources", would see an unknown URL, would click on it, would find themselves on a new website - and might become the website's newest customer. Owners of new websites learned that one way to get initial traffic was to surf to every blog and website that they could find, in hopes that the blog / website owner would check their logs, and would return click to their blog / website. Spammers learned this trick too.
Some blog owners, who proudly display the URLs of their referring sources, contributed to the problem which we see now. The search engines index the access logs published by the blog owners, which contain the compressed URLs such as "bit.ly" and "goo.gl", and link to the actual website published by the porn spammer in question. This leads to search engine indexing of the spammers website.
Recently, spammers developed techniques for automating the surfing. Instead of actually loading even the main page of our blogs, they simply generate a script which simulates contact with the Blogger servers, and run it from their server, in quantity. Stats records the initial hits, and saves the referer URLs. We look at the Stats displays, and wonder.
It's even possible that the computers that we see reflected in our logs - Latvia, Poland, and Russia - are being controlled by porn spammers who live in England, Germany, or even the USA. Even spammers don't crap where they live. Referer spamming involves massive amounts of fake page accesses, against multiple websites. A botnet would be a natural tool, for a project like Referer Spamming.
If you use a product like Google Analytics, you can write a script to filter the odd URLs out of the Analytics displays. You can get the same results with Stats, by ignoring the spam, and working on publicising your blog. People with blogs with low volume activity will notice the mysterious URLs more, and will worry. People with blogs with high volume activity will recognise the mysterious URLs, will know what they are about, and will go about their business.
If the volume causes unwanted traffic to the Blogger servers, Google Engineers will block what they can. Other than that, don't click on the links, don't publish your access logs or statistics, and get back to work.