How is a website like this able to use these images?

http://talkingcomicbooks.com/category/comics-2/marvel/
If I wanted to create a similar site, wouldn't I have to abide by copy writing laws if I wanted to use things like covers of X-men or art work from D.C. comics? I see similar images on lots of comics related sites and I usually never see any mention of a source for the image. Couldn't anyone just use the same pictures, change the alt tags and maybe re-size and be protected from a lawsuit? Images from comic blogs/sites aren't from places like Shutterstock or Flickr. Can somebody give me any good ideas about this? Thanks

They most likely will cite fair use laws if anything goes down. The review articles don't have the entire comic in the post. The articles count as commentaries or critiques of the work. With fair use being such a gray area I'd say that protects them.

Hosting archives of dc comics etc. would be where you could attract much more heat.