We have common sense & can pretty much connect the dots and say its Halo 5 at this point without feeling like its jumping the gun theres enough evidence there. Why the title was changed is another story, your right in saying that maybe 4 was the last numbered title and that from here on out we will have book-like titles for Halo games, I mean after all it does get ridiculous if you use numeral titles without using the cliche roman numerals.

Or it could be that they didn't want to announce Halo 5 their at that crash-and-burn of a conference yet but secretly announce it at the same time. say that a halo game is coming and lead people on until their next big Halo centric event when they will reveal it was Halo 5 the entire time.

Who knows what the reason is, all I know is that I'm not buying the fact that this is some Halo game completely unrelated to the numbered games like they have been saying. and this video just proved it...