If the MBA had firewire, a 2nd USB port, and ethernet, it would be the PERFECT replacement for the MacBook.
It's lacking almost every port imaginable, however, so it won't work for anyone who just wants a desktop replacement.
If it won't work as a desktop replacement, it'll never work for the pro crowd..
So, that leaves us with the consumerist who's no more advanced then your average tween. My dad, for one, would see it, think it looks wicked cool, never ever know what firewire is.. and get it.
Actually, most people probably would. Heck, I would, if I could afford it.
and then he'd have to get another mac when he finds out he can't use his camcorder with it...
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In this day and age, a desktop replacement isn't something with a 5000000ghz CPU and 24657567MB's of RAM, it's simply a computer that can function as your main computer.