Performance hasn't changed for me, but my system's GFX is laughable and apart from a few connection drops, the session was remarkably trouble free.
Levelling is slow going, which takes a little getting used to and ranged is still king, especially once all the spell effects and zerging starts kicking off. Some public events were mental, especially against champion mobs. Yet once I'd strayed in to the next Norn zone, it calmed down and some encounters became very entertaining.
Tried a bit of crafting too, but it's not something you can really get too far with on a quick evening session.