Absolutely nothing has changed - the forced collection of sales tax by one state against a purchase in another state is still unconstitutional. Quiill vs. ND is still the legal authority and there have been no rulings by any courts that have reversed this.
What has changed is that states are atttempting to get around the SCOTUS ruling by stretching the definition of nexus beyond the breaking point, claiming that "affiliates" and separate legal entities owned by the parent in that state are sufficient to create a nexus.
In the case of affiliates, Amazon and others have told the states to pound sand and stopped paying affiliates in those states. In the case of distribution centers and separate legal entities (read: software development centers), Amazon has chosen to negotiate collection terms with those states. Fine as far as it goes.
The legislation that someone referenced earlier in this thread is an attempt to create a new national sales tax that would be applied to transactions that are not currently taxed at by states. And if you think it would stay that way, I have a bridge I'd like to show you.