hasthelargehadroncolliderdestroyedtheworldyet.com has a news feed. It also has this in the source:

if (!(typeof worldHasEnded == "undefined")) {
document.write("YUP.");
} else {
document.write("NOPE.");
}

Folks without Javascript get a more definite answer:

<noscript>NOPE.</noscript>

Also appreciated:

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