"Apple could still offer authorized applications through a Mac App Store without blocking applications that are distributed directly."
So you're saying that they can still offer an AppStore for the Mac/Macbook, with approved signed applications ON TOP of what we already have now? I don't see what's wrong with that.
You could always not use it if you worry about not being able to pirate the apps.
I like how Apple has organized the App store they have now. I like to read reviews and see what popular applications are from normal people. I think it would be a good idea yes as long as its not locked down like the iPhone OS.
It's easy to customize the ammount of information you would like to customize.
I think you can either add settings while composing an e-mail or you can set those as a preset.
There's nothing cool with that unless you really need to set different kinds of recipents and whatnot...!
Not that useful IMO.
In the Mail app (top menu items): View--Message--Long Headers. You can switch back and forth between Default Headers and Long Headers for each individual message.