It's cute but completely unnecessary and will probably end up with half the programmers not coding for it anyways. Although considering Nintendo is doing it, first party games will almost surely use it a fair deal in rather entertaining ways, as they've done well with every other gimmick so far.
Kinda like the touch screen but far easier to ignore and not actually useful for any gameplay mechanics.
At least, that's my theory.
It wouldn't be the first time a gimmick has been largely ignored, see PS3's motion controls.
As to the rest...hah, GC powerful. Sure, Nintendo has been known to make the most powerful handhelds on the market. There was the Gameb-...um, Gameboy Col-....er....the D.... GBA was the only one that ever led the market, and that was by default-it had no competition.
GC-levels of power strikes me as way too high of a guess, particularly as the DS is strikingly low power(Overall less than a third of the PSP and the poly counts are hideous comparatively.). I'd bet on something more PSP level, maybe a bit lower. Might be being too under-generous to Nintendo, they *have* been making a lot of cash lately and the thing holding them back *has* been processor power, for dominating the market.
Forcefeedback/Accelerometer... sure, believable as hell, Wiimote has both. Doesn't bode well for the base cost being as cheap as the DS, but 200$-250$ for a DS is still on the reasonable side for a launch console. I suspect that the eating through batteries part may be not considered too major. Honestly, relatively few people seem to complain about the PSP, and that's a battery hog. So I dunno, I can see it. Then again, it's a logical enough addition that indeed someone may have just BSed it up. So, who knows.
How would you fit a joystick though? Would you ditch the closeable clamshell-type design? Meh. Some kind of PSP-type nub thing maybe, but those aren't much fun to use anyhow(Which is why PSP games so often use it as a secondary control option or default to D-Pad and use it like the C-Stick on an N64.).
