"Went missing is perfectly fine."

"Wiktionary (a blend of the words wiki and dictionary) is a multilingual, web-based project to create a free content dictionary *of all words in all languages.*" (emphasis mine).

It appears the authoritative declaration of correct grammar went missing.

Regardless, the phrase grates on the ears and it appears that a lot of people hearing it have gone tired.

Journalists are notoriously unskilled when it comes to english usage and grammar. There's a show teaser currently running on television wherein the reporter states, "I've learned...that all is not what it seems." In other words, *everything* is an illusion. She really means, "Not all is what it seems", though there are better ways of conveying that intended message. Apparently neither she nor her editor know the difference.

"Gone missing" has a "street" ring to it and causes the person saying it to appear lacking in education. If this is the sort of thing they were taught in school it's an indictment of our education system. Then again, maybe they're attempting to appeal more to the uneducated.