I had 3 items that gave me 31% IAS;
1) Boj Anglers --- 12% before, now gives 5%
2) Rare Ring ----- 4% before, now gives 2%
3) Rare Gloves --- 15% before, now gives 7%
For #1, I honestly don't know what happened, but for #2 and #3, I believe that they used a "Cut in half and round down" change... I think they should have left it at a cut of 50% max, since a cut any higher than what they had stated would obviously cause an outburst of anger. That makes me believe that they should have done it "50% rounded up", that way 50% would be the max it would drop. (I still think that 50% is still too much of a drop though). As a basis on this thought, I had 31% IAS before and I now have 14%. Half of 31% is 15.5%, therefore people will complain about it.
As for my Boj Anglers, I honestly don't know why they dropped more than 50% rounded down. Was this intended?