We've discussed this before, but this is a good reminder, Andy. It's a perfect illustration of the importance of being precise and paying attention to details.
Both of these laws were passed in the same omnibus package of legislation, so you can easily mistake COPA (pronounced with a long 'o', like in 'cold') for COPPA (pronounced with an 'ah', like in 'Congress').
The names are confusing, too. COPA's full name is "Child Online Protection Act", while COPPA is the "Children's Online Privacy Protection Act." It's very easy to pick up pieces of the names and mistake one for the other.
COPA was struck down because it prohibits speech. COPPA will survive because it simply requires disclosure and opt-in--like ESIGN and other familiar laws.