The Nintendo 3DS has been pulled from Amazon in the US and has been placed “under review”.
On the UK version of the site the 3DS is still available to purchase however on the US site the following is displayed;
“While this item is available from other marketplace sellers on this page, it is not currently offered by Amazon.com because customers have told us there may be something wrong with our inventory of the item, the way we are shipping it, or the way it’s described here. (Thanks for the tip!) We’re working to fix the problem as quickly as possible.”
I would appear that there is an issue with how the 3DS is being shipped to customers.