Let's call it a 5.5.
There's a lot I've seen that I really like: the new trade system, resources, commanders for units, cities and towns, independent powers, navigable rivers, the attention to detail for Mississippians and Shawnee, and more.
There's also a lot of things I really dislike: the civ designs, the concept of civ-switching, the sharp age transitions, the new leaderscreens, the UI, and that god-awful leader roster (ESPECIALLY Ibn Battuta and Macchiavelli).
In general, I regarded the nuts and bolts mechanics of the game with a lot of appreciation while the stuff they're really marketing with abject horror. I'm getting a lot of whiplash, and it continues to grow.