There are a few.  The introduction of resource credits showing that everything we do bears some form of cost. The bandwidth was an issue a few forks back and hasn't really been spoken about until now. Account creation will be made a little cheaper by using these credits.

 The platform is trying to cut out the spamming which are coming from small accounts. By reducing what a small account can do without investing was the idea. That didn't go to plan and there were some complaints from genuine users who were now limited. A patch was introduced to strike a balance last night and so far so good.I think there will be some little changes coming as after the patch was activated last night some spamming accounts were active again. I can see the resource credits being played around with over the next couple of weeks.

Curation ,concentrating on authors who were self voting . If an author self votes like they used to as in immediately after posting that vote is now wasted and is basically burned. The safest is to wait until the 15 minute mark if the author wants to vote now.

Dust votes or very small votes are also lost now to a taxation so care and thought need to be applied on what and how much you are voting.

This is my first hard fork and i have learnt quite a lot on why and how it is needed for the preparation of SMT's next year. I am sure by March we would have seen a few more additional changes to get the system performing correctly.