Nintendo is definitely aware of the piracy on the DS– flashcarts that allow players to download games onto a memory card to play on the DS on custom firmware. It seems that Nintendo may be taking matters into their own hands on piracy for the 3DS. Japanese retailer Enterking has posted a warning about the such, however, whether it is from Nintendo’s intentions are unknown.

The warning is translated to such:

Dear customers who seek to re-sell the Nintendo 3DS,

“In any case where you use equipment which is illegal or unapproved by Nintendo, or if you do customisation [of Firmware] which is unapproved by Nintendo, there is a possibility that Nintendo 3DS become non-bootable by system update.”
- From Nintendo 3DS terms of agreement

Due to the terms of agreement above, Enterking refuses to buy Nintendo 3DS systems that have any record of the use of illegal or unapproved equipment.

To protect from leaking your personal and internet connection information, we ask customers to format their system before selling it. If we refuse to purchase after you format your 3DS system, Enterking is not responsible for any lost data and settings. Please understand before you format.

In any case, this means that your 3DS may be bricked if you try to hack, and that the 3DS can easily discover piracy via official updates from Nintendo. I guess this is a warning to all gamers.