Nintendo has released a new firmware update for the DSi which blocks the use of several flash carts.
Nintendo says the update, version 1.4.1U, "provides behind-the-scenes improvements to system performance", but its sole purpose appears to be blocking the use of flash carts which are widely used to run illegally downloaded games on the portable.
The update adds no new features to the console whatsoever.
GBATemp (via Joystiq) says the carts confirmed to be affected so far include: Acekard 2i, Supercard, DSTwo, M3i Zero, iPlayer and the DSTTi. However the EZ-Flash Vi, iSmart DS and Hyper R4i are reported to still be working.
A ruling from the High Court in London officially outlawed the importing, advertising or sale of R4 cards in July. The cartridge - which was made illegal in Japan in February - allows DS owners to transfer digital games downloaded on a PC to their console, including those pinched from Torrent and P2P sites.
Update: It looks like the Wii has also been given a piracy-banning update.