M59 Coming..Where's M58?

The Inquirer is running a story this morning that gives us a very brief preview of ATI's upcoming R580-based mobile GPU. Likely dubbed the Mobility Radeon X1900, it seems safe to assume that this new flagship mobile part will best NVIDIA's current GeForce Go 7800 GTX GPU. Obviously, the frame rates of the available NVIDIA GPU will certainly be faster than the 0fps of the unavailable part. However, the most interesting question within this story is, "What happened to M58?". 

It was not hard to get this one as M58 was the codename for the still unannounced Mobility Radeon X1800. We have seen this chip more than once already but we don't know about any design wins.
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