If it gets confirmed that those are parts of the 772 it's a good start. Also, if it is indeed a 24 m part of the fuselage still intact it means that it wasn't a violent impact with the water.
I wouldn't say it was an attempt of a planned ditching but that big chunch of fuselage wouldn't be in one piece after a full speed, uncontrollable impact with the water surface. However, Im just speculating, hopefully we will know more soon.
I believe Aussie are to be congratulated for their efforts. I saw on the news that they deployed some jet fighters to try and get a confirmation asap.