It’s not particularly surprising, but the 3DS XL will find the original Circle Pad Pro to be a more than a tight fit. According to Famitsu, translated by Andriasang the original Circle Pad Pro is not compatible with the 3DS XL, and a Circle Pad Pro XL will be offered for the plus-size 3DS sometime this year.
The previous version of the Circle Pad Pro will only work on the current version of the 3DS, which, while being a point of pride for the handheld which decided not to eat all the pies, bodes badly for anyone who purchased it and planned to use it with an updated version of the handheld later down the line. Once Nintendo has sized the 3DS up, barring a large negative response, it’s unlikely they will put it on a diet in future editions.
The charging dock which came with the original 3DS probably won’t fit either, but Nintendo may opt to include a size-fitting dock with the 3DS XL.
Famitsu also mentioned that the 3DS XL will be compatible with the data transfer feature of the current 3DS, so those who plan to buy the bulk won’t have to lose their saves and eShop purchases.