If you go to www.nintendo.com/consumer/systems/3ds/en_na/3dsambassador.jsp then click on "Troubleshooting" on the left side of the screen and then "The Ambassador News Article in the Nintendo eShop Is Gone", you get this answer:
"The News Article in the Nintendo eShop stating, "You Are A Nintendo 3DS Ambassador!" was removed prior to the Nintendo 3DS Ambassador program deadline as only systems connecting before that time were eligible.
If you connected to the Nintendo eShop or performed the latest system update before 11:59pm Eastern August 11, 2011, you will be able to download the first ten free games being offered on September 1, 2011.
If you are unsure of your Ambassador status, you can check back here later next week for more information on checking your Nintendo 3DS Ambassador status." --- What's your Acceleration Style? 3DS Friend Code: 4296-2944-2414