Meanwhile I'm agonizing over $300 bucks on storage and RAM for a macbook air. Not even a Mac Pro rounding error.
Welcome to the big leagues. Keep in mind, those do not line up to buy these machines, they can afford to hire someone to line up for them.
While I'm sure the custom, high-end, PC types will balk at this price, the professional media editors that most of these units sell into don't even blink an eyelash at this price.
For the cost of a top end Mac Pro and a third party multi terabyte disk array, you have the hardware to edit a major motion picture, television show at the fraction of the cost just five years ago. I expect to see a big boom of independent films and other shows come about with this tool on the market.