DS2 is obviously going to be compatible with DS games. I don't see any reason Nintendo would do without.

PSP2 may not have PSP compatibility. Why? UMD.

DS have the huge advantage due to the game cart. It's small enough to comfortable fit into a new DS2 design.

DS2 could keep the same size cart as DS and make the slot a 2-in-1, which further add flexibility to designing the hardware.

PSP2, I don't see it carry over the UMD as it would retain the spinning mechanism. And it will be a bottleneck to add PSP compatibility as it would require a different slot. Something like the current DS slot1 and slot2 but the UMD is much more clunky.

If PSP2 chose to do away with backward compatibility, that would surely put it at much further disadvantage.

Your thoughts? 

Mock up DS2 

This images are so cool, but this new DS is too tiny.

Im not even going to bother with nintendo, their games are going backwards not forwards, i mean look at the game on the DS2, clouds with faces on them...wtf and the track is shaped like Yoshi, fuck the whole lot, nintendos games are for pre school kids.

ds2 looks like a cluster of doody.

After the DS lite was created they cant give a less sleek look to thier next gen handheld.