Full retail games can now be downloaded to Nintendo 3DS in Japan, but there was a problem or two early on. Nintendo's online service page reported server troubles on the eShop shortly after launch, though it's now been fixed.
Andriasang reports that the eShop issues came between 9:00am and 11:30am on the service's launch day. It shouldn't come as too much of a surprise, given that the first two games released in this way are the sure-to-be-massive New Super Mario Bros. 2 and Dr Kawashima's latest outing, Demon Training.
Let's hope that this doesn't become a regular thing and that there are no such worries when New Super Mario Bros. 2 comes to the West next month.