I'd be willing to bet this is going to be the No. 1 line on the whole 1040 that gets messed up. There are a lot of partnerships and pass-through entities that qualify ... there are more people affected by this line than you might think.
They basically just got rid of the flat definition which said a foster child is any child you care for as your own and cared for the entire year. In a way, a lot more people could qualify for the Earned Income Credit than did before.