Just popping in to say no, I've never even seen that Wordpress blog.
'Prometheus Unbound' is, as other people have pointed out, the title of a play by Percy Shelley from 1820. If you have any familiarity with Eng Lit, it's also about the most obvious thing to call an expository article about a film called Prometheus, which is why I, this other guy, and stacks of other people have all done so.
Also, the word 'eponymous' means 'that for which a thing is named', in this case, the movie. If we were discussing the movie Titanic, the Titanic would be the eponymous ship. I can understand you might think the term was copied if you weren't used to seeing it used often, but I'm afraid that terms like that get bandied around a lot. I use a pretty broad vocabulary. Pan back through my LJ and check out my other work, you'll soon see what I mean.
On top of that, the content of my article and his article are completely different. As in, none of the content is the same. I go on about the Golden Bough, Space Jesus, the black goo, themes of sacrifice and acceptance of death versus unnatural extension of life, and what I think the answers are; he talks about Milton, the space cobra thing, David, and how nice it would be to have some answers.
In short, your accusation of plagiarism is based around the title, drawn from a common source (Shelley) in each case, and the fact that we both use a word - 'eponymous' - that you apparently didn't understand.
Hope that clears things up for you.