I keep seeing an increasing number of blogs that have been created for the sole purpose of hosting guest blogs with no other content but guest posts they have acquired. A lot of these blogs are monetized with Adsense and have a pretty spammy backlink profile. For instance I cam across one of these sites with a PR of 4, but if you look at the links they are all bought .edu and .gov comment links etc. Some of the blog will have an even worse profile simply a scrapebox blast at the url. My question is do these blogs make any money? They host an absolute ton of content and have a ton of backlinks and there seems to be a huge proliferation of such blogs, so are the guys making any cash worth writing home about?