The only guarrantee I can make to you is that if WOTC's R&D is currently thinking about 5e, that 5e will not look like what R&D is thinking about right now.
Reviewing 4e's design history is a perfect example. The original concept of 4e was similar to Star Wars Saga Edition...but over time the system evolved into what we have today.
5e will go through the same process. It will start as X, and eventually evolve into the finished product Y.
And there's still a lot of development time to see what new mechanics come down the pipe.
Think about all the big design changes we got towards the end of 3e, swift and immediate actions, spells with variable casting times, magic items with codified levels, completely new models of spellcasting (such as the binder and the shadowcaster), a completely new model for martial classes with BO9S, tactical feats, etc. All of that happened in the last few years of 3rd edition.
Who knows what new 4e mechanics will evolve, and how many of those we might see polished in a 5th edition.