It's already said to be $250 for the non-3G version and $300 for the 3G-enabled SKU. It is rumored that the price might even go lower, too! I'm thinking, though, that $250 is a fair deal. $250 was way too much for the PSP-1000 and people still bought it. I think it's there to stay.
Just think... Who would buy a 3DS vs. a PSP2 if they are the same price? That's what I thought. What if Sony sold it for $230?? Nintendo would be so mad.