Yes, I really think anyone outside of Nintendo would be making a mistake launching a system, especially in this economy.
Sony, especially, would be unwise to launch the Orbis. The PS3 is selling strong, and the gap between the 360 is very narrow and/or non-existant at this point. They have a lot of momentum with the PS3, they need to keep it up, and focus a lot of attention on saving the Vita.
They could do themselves a lot of favors by not supporting the PSP in Japan anymore. That's hurting them, I think.