Nintendo president Satoru Iwata recently confirmed that the first 3DS firmware update is due during May, rather than at launch.
Just a week ago a representative from Nintendo Europe had claimed that the additional software would be available as a download on day one. However this isn't the case as Iwata today confirmed that the additions, which also include the DSi->3DS transfer function, are out at the end of May "at almost the same time around the world".
The 3DS's software store will also offer demos and trailers like the Nintendo Channel, as well as 3DS software and virtual console releases - essentially the Wii Shopping Channel and Nintendo Channel's rather beautiful offspring.