I just got a MBA for classes and such, it is literally the size and weight of one of the smaller notebooks I carried for work. I would definitely recommend it and for note taking and even some simple work it's the perfect machine.
Is there anyway that you can just ditch the backpack though? I can get through all of my classes with a small notebook and my computer. Heck, if the weather wasn't dropping snow I would just carry my Air and put the power charger in my pocket.
Give it a week, I don't even think about hitting the right button anymore, just let the fingers fly and the thing corrects as you go.
Might not be perfect, but its better in my mind then having 2 laptops. Unless you really just want 2 laptops, and can afford 2 laptops, then what the hell, go for it.
My MBA Rev A is my only notebook. Works like a dream. I watch movies on it all the time. Sometimes youtube can be skippy cause of the flash, but not really. Ignore the haters.
And it is a huge difference between macbook and mba. i could never carry a macbook 24/7 like i do with my mba.