Kill the MacBook, yes, but do not change the name of the MacBook Air, and lower the price of the MacBook Pro models by 100USD across the board.
The basic question is... is the MacBook a profitable item for Apple currently? Is the demand sufficient to justify its existence?
Without concrete answers to these questions, how can we call for the demise of a product line...?
"Hey, Apple, why don't you cancel a product line that's wildly successful and profitable because I don't imagine I'll be buying one."
That's kind of short sighted in my view... There are lots of ways the MacBook could evolve, while remaining relevant, sleek and an amazing entry-level Mac that will may very well lure people into upgrading eventually to the MacBook Pro...
My advice to Apple: do what the data tells you to do.