This does seem to lean more likely towards the album actually happening, MM being a part of a track on the album puts a responsibility on Yoshiki to not let down his friend in terms of release timing, and letting him down could cause word of mouth to spread amongst western musicians and impact his and the bands reputation. On top of all this it feels like Yoshiki has finally come to the end of producing/finalizing all the new songs for the album over the years, we haven't heard 'La Venus' for a while, but Hero/Beneath the Skin when you hear them live sound like they've been pretty much finished for a few years now, and we got a much more full version of Kiss the Sky on the acoustic tour, though there's much more to that song still apparently.
It just seems like it's coming together, the first half of the new songs, I.V, Jade, BTBF, Without You ect. were finished years ago (wish Scarelt Love Song was a part of that, some of the best atmosphere I've felt in an X song, too bad.) and now we have the other half of the new songs that have been peformed live for years and sound good, really feels like their done and the mixing's being finalised to me.
Only thing i'm concerned about with this release date is that this song with MM sounds like a new one, so that's a whole new song yoshiki's got to complete as well as the mixing of the whole album by the end of the year (though most of that should be done now already imo), I think that's perfectly reasonable and comfortable for someone who's not being overly picky/perfectionist to do, but Yoshiki is those things most of the time, from what we've been shown.