The Nintendo 3DS utilizes a similar title-based organization as seen in the Wii and DSi platforms. The same update server is being used as was with the DSi, however a new common key has been introduced.
The organization of Title IDs has not been documented fully yet.
Here are some confirmed Title IDs (from the first update):
00040010-00024000 - Promotional video 00040010-00025000 - Promotional video 000400DB-00016102 000400DB-00017102 00040130-00001C02 - Firmware 02_1C 00040130-00002402 - Firmware 02_24 00040130-00002D02 - Firmware 02_2D 00040130-00002E02 - Firmware 02_2E 00040130-00003402 - Firmware 02_34 00040138-00000002 - Home Menu