Just from skimming the wikipedia article, it doesn't seem useful for translating. But it is slightly stronger than "The most frequently appearing words in this pile of un-translateable text are the most common words in the language it is written in." It tells you that, for example, the most popular word should be about twice as popular as the second most popular word.
It doesn't tell you what those words are, but it is a pretty specific observation about the frequency/rank relationship. So, as the wikipedia article liked about points out, it can tell us that the Voynich Manuscript was probably written in a language (of course, it could be a cypher of a real language or something made up, like elvish in Lord of the Rings, but it probably isn't just a random collection of symbols because it is unlikely that a random collection of symbols would happen to follow this distribution).