Does Flickr really own the tag cloud copyright?

We have not told anyone about the start of the open testing of the www.flaer.info project, but the local portal has already accused the developers of plagiarism and stated that (I quote): “... the tag with tags was borrowed explicitly from the concept of the main network photo storage; and even the design is reminiscent of the Flickr interface. ”

Original article

I wonder where the author of the article has information that only Flickr has the right to tag cloud in its concept, and what did the authors of the article see as plagiarism?