Another thing I miss is the near-ubiquitous AppleScript support, at least in terms of major applications. As frustrating as AppleScript is as a programming lang

Another thing I miss is the near-ubiquitous AppleScript support, at least in terms of major applications. As frustrating as AppleScript is as a programming language — speaking as someone who curses it on a near-weekly basis — it's still far easier to reliably automate applications using a reasonably well-defined object model than via UI automation, which is the only viable alternative for most current OS X applications. And for simple tasks, even a problematic common scripting language like AppleScript is preferable to needing to use a different scripting language for each application, even if these languages are, individually, superior.