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):
0004001000021000 v0, v1027 0004001000021200 v0, v1026 0004001000021700 v0, v1026 0004001000021800 v0, v1027 0004001000021900 v4 (added with 2.0.0-2, probably eshop/browser) 0004001000021A00 v4 (added with 2.0.0-2, probably eshop/browser) 00040010-00024000 - USA Promotional video v0, 2048 (size of these video titles changed from 26MB to 131KB) 00040010-00025000 - EUR Promotional video v0, 2048 0004009B00010402 v0, v1024 0004009B00010602 v2 0004009B00012302 v1026 0004009B00013302 v1024 000400DB-00016102 000400DB-00017102 00040130-00001C02 - Firmware 02_1C v1040 00040130-00002402 - Firmware 02_24 v1024 00040130-00002D02 - Firmware 02_2D v1024 00040130-00002E02 - Firmware 02_2E v1024 00040130-00003402 - Firmware 02_34 v1024 0004003000009202 v0, v1026 0004003000009302 v0, v1026 0004003000009402 v6 0004003000009602 v0, v1026 0004003000009702 v0, v1029 000400300000C502 v0, v1026 000400300000C802 v0, v1026 000400300000CC02 v3 0004013000008002 v0, v1028 0004003000008A02 v0, v1025 0004003000008F02 v0, v1027 00040138-00000002 - Home Menu v1472 0004013800000102 v432, v1489 00040010-00020400 Nintendo 3DS Camera (Available on NUS but not in SOAP response) 00040010-00020500 Nintendo 3DS Sound (Available on NUS but not in SOAP response) 0004800F484E4841 v0, v1026