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Eurogamer got the Vita/PSP2 correct (Imagination PowerVR), also I believe Nvidia actually was going to do the 3DS chip, the deal fell through very late in the development process and Nintendo chose Pica200 from out of the left field.
Besides it's not just Eurogamer reporting this, it's now IGN, MCV, Wall Street Journal, and others who have said they have verified it with their own sources.
This is basically like the PS4 Neo and Scorpio leaks, remember how people were saying that was just a rumor ... until multiple sites corroborated it.
I don't really even see what about the rumor is so surprising. Nintendo can't even support the Wii U and 3DS as seperate entities, you seriously expected that they were going to support an even more powerful PS4-tier console and a PS3-tier portable? Not a chance in hell. Something was always going to give and it was always going to favor the portable market because the 3DS has sold 5x more than the Wii U and every Nintendo portable has sold more than its console countpart for the last 20-25 years.
