A CRNA is just a glorified and right now an overpaid technician.
From what I've seen, nurses are great at shooting themselves in the foot. They will keep opening more and more schools without much regard to market demand. This is an interesting thread about NP's complaining how their salaries are a little more than an RN's because there are more NP's than there are jobs.
http://allnurses.com/forums/f34/np-making-six-figures-40528.html
They even gripe how PA's are contributing to stagnant NP salaries. I predict that something similar will happen with CRNA's. More CRNA schools, more states licensing AA's, and more AA schools opening up. At some point, there will be more anesthesia providers than demand. They will really realize that they are technicians when their attempts at scope expansion fails. They will then be stuck just delivering gas in a declining reimbursement and rising malpractice environment. As Blade said, anesthesiology will become more supervisory and it will be forced to move up the medical value chain.