As I thought yesterday, the change with the highest implications and which will need a longer time to find its optimal parameters is the new resource credits system.
A confirmation for me came later, when I read @steemitblog's update announcing what to expect for the next day (i.e. today, in about two hours as I write this).
So after the hard fork, if everything goes well, a few things should be clear:
You can read details about every one of them here.
What will be still be in a kinda fluent state for a while is everything connected to the resource credits system. That influences every operation an account can do on the blockchain, including the newly introduced possibility to create new accounts using RCs instead of paying for them with STEEM.
While the next week or so may not be the greatest from the user's experience, especially if you have low SP or you have a highly active account (one that runs a bot for example), this is a necessary step to calibrate the real consumption of resources on the blockchain in the perspective of scaling up.
Tic tac, tic tac! Less than 2 hours now... :)