It is back on the kids menu as of the 4/07 updated menu at wdwinfo.com.
I don't have any personal experience with adults ordering from the kids menu yet, but the CM I spoke to about the dining plan said that DS would be able to order kids' desserts if he wanted, even though he'll be an adult on the plan and ordering adult entrees. I was concerned that he'd want the 'make your own sundae' rather than creme brulee or such off the adult menu, so I asked.