scource: http://www.gameranx.com/updates/id/23907/article/rumor-new-3ds-hardware-specs-details-leaked/ and http://alwaysnintendo.com/rumor-new-nintendo-3ds-specs-leaked-codename-revealed/
So we all know the New 3DS will be more powerful than it's older brothers, so I did some digging. These 2 websites claim to know the specs of the new 3DS through dev kits.
Rumours are: triple the clock speed, double the FCRAM, same GPU and same VRAM (although many other scources also claim an extra 4 MB of VRAM)
Compared to the older models this would mean:
CPU would go from a dual ARM11 MPCore clocked at 268 Mhz and a single core ARM9 clocked at 134 Mhz ---> dual core processor clocked at 804 Mhz and a single core processor at 402 Mhz (L2 cache would be added as well)
GPU would stay the Pica200 at 268 Mhz (no real surprise, the Pica200 is plenty of powerful enough for the 3DS)
RAM: 128MB of FCRAM (fast cycle random acces memory) and 6MB of VRAM (video random acces memory) ---> 256MB of FCRAM and 6/10MB of VRAM (different rumours point to 6 or 10 MB's of VRAM)
Do note that these numbers are all speculation and that they are in no way a definitive measurement of performance.