As DSiWare begins to fade into the eShop background, we get some confirmation of its size.
http://www.nintendoworldreport.com/news/26554
The limit on DSiWare games is 16 megabytes, according to an anonymous developer source who was limited by the restriction.
The news was previously known, but the re-confirmation of the restriction is a reminder of the limitations of the service, which will be available on 3DS systems tonight when the next system update opens up the eShop.