Judging from install reports in the aftermath of the Leopard release last week it appears that Leopard is much more demanding on system hardware — in particular RAM. From comments left on this blog, Apple support forums and elsewhere dodgy RAM rather than install media appears to be one of the leading causes for the previously documented install failures.
This bears out my own experience. The Apple Store has had my non-Leopard-installing G5 for nearly a week. First, they were convinced that it was the hard drive; order a new one, replaced it and still couldn’t get an install. A call on Friday informed me that they now think it is the RAM (Apple, factory installed RAM, mind you) that is the issue. The new RAM is on order so it will be sometime next week before I find out whether that is the final glitch.
My question is: What is Leopard doing that is uncovering these RAM issues now? These issues are apparently errors/failures that 10.4.10 (and previous) didn’t seem to care about. Could it have something to do with 64-bit app support? Fundamental memory handling tweaks or changes? Will there ever be an in depth root-cause analysis that gets published by Apple?