No way! They skipped over the 540? There goes my speculation... Anyway, in an effort to expound upon this topic a bit, I'd say it's a safe bet that the next Sony console will be called the Playstation 4 (what else?), and Microsoft, if they decide to make another console, will probably be called the Xbox {something}. As for Nintendo, well, most likely their random letter sequence generator is being tuned up for the next generation. I don't think Nintendo's next console will have anything to do with the Wii's name. Sort of like Sega that had the Saturn, then the Dreamcast, Nintendo launched the Gamecube, and then the Wii, even though the Gamecube had an awesome reputation. It's hard to say the same for the Saturn, but it wasn't all that bad.
So yeah... that's just some ideas of mine.