I must say I can't really understand how some people seem to believe that for example HLH is not the final version, unless you have heard otherwise on radio.
Sure, I was also confused when I heard it first (on its own, outside the album), but it all made sense as MX emerged to HLH. They fit together pretty well if you ask me, I barely noticed the transition.
I'm really looking forward to when the album is "properly released" here in Sweden a week from now. Will we hear any differences once Mylo Xyloto is officially released around the globe? Who knows?