Is Mach-O on OS X or ELF on Linux any more or less sad?

Don't know about Mach-O, but ELF is actually a rather nice and clean design.

Much of the hate PE gets is because of the silly overloading with .NET assemblies.

Oh yeah, and now also WinRT metadeta.

It annoys me mildly that .NET requires you to have a little native stub in assemblies, but the Windows loader does not actually execute it.

It annoys me more than just mildly to see .exe and .dll on linux. And that silly native stub!