Today I ran across one more reminder of how screwed up the entire migration strategy was. From Apple's current iChat documentation (emphasis mine) ...
Mac 101: iChatOk, except .Mac accounts don't exist any more. (And AOL is going down, but that's another story.)
...To use iChat, all you need is access to the Internet and one of the following: A .Mac account or a free AIM (AOL Instant Messenger) account. Here's how to set up and use iChat...
The page was last revised "November 21, 2008". Four months after MobileMess.
.Mac was deeply embedded in Apple's operations. It's distributed throughout the OS, it's everywhere in their documentation, it was integral to their identity management and thus their DRM (Apple's identity and account system was still screwed-up a few weeks ago -- thanks to the migration).
The .Mac to MobileMe transition wasn't a routine "we're-off-by-a-month" screw-up. It was a titanic "we're-off-by-a-year" screw-up.
A disaster on this scale should have led to a top-to-bottom internal post-mortem, but I suspect Apple has simply executed a scapegoat or two. This was too big to be one executive's error, and it suggests Apple's shakier than most of us think.