Nintendo stated out of E3 that their goal is to match the battery life of the DSi, which is approximately 14 hours on the lowest brightness setting.
If this is the real deal, those are some solid numbers. Offhand though, without any extra information, the GPU spec doesn't say a lot. We have heard that the 3DS, in comparison to the GameCube, supposedly is capable of fewer polygons but is superior at producing certain graphical effects like bump mapping (got no clarification for that, may have heard it on a podcast). It's a shame there was no detail on the audio processor; I'm interested to see how much of an improvement that will have over the DS, assuming it is an improved sound card et all.