Wow -- I missed that rule change, too. In fact, I just changed an award ticket date (but I'm platinum, so I guess there's still no charge). But if one of my kids redeems an award and we want to change a date, I guess I could be looking at $35 or $50.
Not very nice, IMHO.
But hardly surprising these days, given you can't change a regular leisure ticket for less than $100.