First off, these aren’t really changes, they are additions. These can all be stripped away and we will still have the Halo we all know and love. And I think we will be able to play H4 that way too. The ranked, competitive playlists are going to be fair and balanced, whereas the social side of MM will include the new stuff.
There is a lot of comparison to COD and these additions are blatantly to attract gamers from other series. This is a good thing though. In terms of popularity Halo has been declining and H4 is going to turn that around.