The 11" will be the big seller id imagine for 2 big reasons.
1. The size of it. It really is small and if you don't have any heavy usage i can imagine lots of people wandering into an Apple store and preferring the small size and great build quality over the standard MacBook
2. Price. Don't underestimate the price. It is cheap. Obviously the processor isn't top of the range but for web usage, iTunes etc it should be fine. A lot of people thought that a smaller machine would be more costly, because its more of an ultra portable. However Apple have managed to position it at the bottom end of their price structure for laptops.
For a second macine, someone new to a mac or a road user who has to have OS X it will be should hit the right note.
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