We see things through rose tinted glasses.
When we use a language where "Buffalo buffalo buffalo Buffalo buffalo Buffalo buffalo buffalo" is a valid sentence, you got to wonder.
English, as She is Spoken, also has a low information density, in part due to the vowel falloff. Most languages have far more vowels, and distinguish I and Y sounds, and O and deep O sounds, and also allow stress on more than one syllable, or intonation distinguishing between words.
In writing, well, I think English is losing because of IMspeak. We're degenerating into a written language that's more ambiguous than precise. Punctuation is being replaced by the universal punctuation symbol "lol", case is disappearing, and abbreviations (sorry, I mean "abbrevs") are more and more used, quite often incorrectly. I'm just waiting for newspapers to pick up with articles like"us sk8 ftw lol us >> finl& lol".
But as long as Hollywood can churn out movies, English, or at least the American version, will still be strong around the world.