Surprise, surprise. According to a user over at Chinese site Hacken, who managed to lay hands on a DSi ahead of its November 1 street date, the new handheld is incompatible with all current slot-1 flash carts. Various cart brands were tested, from the popular R4 to CycloDS, with each repeatedly failing to auto boot. Only one cart in particular, the EZ Flash V, was detected by the DSi (in other words, it was recognized in the main menu screen). However, when launched, it simply throws an error message.
All in all, not a surprise, especially considering Nintendo has pressed legal action against the manufactures of these flash carts over the past couple years. On the upside, this means piracy will be a non-issue for now. Unfortunately, it also means legit homebrew applications will no longer run until a workaround is found.
[分享] 道高一尺，NDSi 正式封殺燒錄卡 [Hacken]