The first two games that come out on the US version of the new DSi Shop will be the two Brain Training titles, Nintendo of America said yesterday.
Nintendo UK has told Eurogamer that it is too early to comment on the DSiWare line-up for Europe.
Meanwhile, 1UP notes that Fils-Aime said titles downloaded from the DSi Shop to the SD card plugged into the new handheld will be playable whenever you want, which we'd assumed anyway, but you never know with Nintendo.
The American site also speculates that you'll be able to download the games again if you then delete them, since that's how Virtual Console and WiiWare operate on Nintendo's other, mildly successful home videogames console.
Oh, and if you're currently staring at the screen in confusion and terror, you might want to check in with the Nintendo DSi announcement to see what all the fuss is about. Short version: bigger screens, tiny camera, SD card slot, no GBA support.