GoNintendo:
Here's an interesting bunch of rumors for you guys. While we already know that various flash carts work on the 3DS when playing DS games, it seems like that might have been planned from the beginning. Rumor has it that the 3DS can actually keep a log of activity that will make note of whether a flash cart was used or not. Furthermore, retailers will be able to check this log, and if they see pirate activity they will not be able to do a trade-in.
That's not even the worst part. We're also hearing that the 3DS will see an update that will block the system from booting up if you've used a flash cart. In other words, if you're playing a pirated game, Nintendo could send out an update that kills your system! Finding a workaround for that might be a bit tough, and quite bothersome as well.
Finally, the last rumored update is one that pertains to curse words on the 3DS. As you know, the system currently accepts curse words and other dirty language when it comes to naming things on the 3DS. It seems that an update is on the way to squash that kind of activity. Thanks to Ruf for the heads up!