[citation][nom]edelgiud[/nom]or is the DSi XL have more[/citation]
As far as I can tell, the DSi XL is basically just a size change; the internals are 100% identical. The same CPUs, (ARM7 @33MHz & ARM9 @133MHz) same RAM quantity, (16MB) same integrated flash storage. (256MB) (and likewise, same single SDHC slot, and same lack of a GBA slot)
The only differences this will get is a bigger screen, a bigger stylus, and apparently a bigger battery, too, as Nintendo appears to be claiming a longer battery life than the DSi on equal brightness settings.