Beyond3D recently made some rather disturbing comments in regards to ATI's R520-based flagship notebook GPU. Apparently, ATI is caught between a rock and a hard place with regards to launching a highly-clocked R520 part when R580 parts will likely be available in the very near future. Regardless, a mobile R580 part would still need to be qualified leaving the high-end desktop replacement notebook market wide open for NVIDIA and its GeForce Go 7800 GPU's for a large chunk of time.
Still left off the list, though, is any type of high end product intended for DTR / mobile gamer platforms. M58 was scheduled to be ATI's next high end notebook graphics chip, expect to be based on R520, and indeed this has already seen qualification on the PCI Express SIG integrators list along with M56, M54 and M52. However, conversations with ATI personnel at the X1000 Series press event just prior to their release suggested that there may not be an R520 based part released. We had previously hypothesised that, given the lateness to the market and its reliance on high clocks for shader throughput, ATI may circumvent R520 and instead wait a while longer to try and qualify R580 for notebook use. A report at Laptop Logic suggests that ATI are readying M59 for release, which is indeed based on R580, however they still expect an X1800 based M58 to launch soon.