The new sets absolutely DO seem to be adding server load and causing issues. The set that pulls you to the wearer, stuns and does damage is the worst. It's like you can see your fps and ms drop to the floor when that procs.
It seems like they added a bunch of insane proc calculations right at the last minute with these sets, and the effect it's having is very predictable. They are noticeably increasing lag and performance issues across the board. Combat bug is back with a vengeance and the bug where you drag your offhand weapon between your legs instead of holding the weapon on your bar is persistent on two of my toons and just won't stop.
- Update 23Ice Furnace: This item set now grants Spell Damage, rather than Weapon Damage for the 4 piece bonus