I flew on a Skywest EMB-120 for the first time in a while and I forgot how loud they were. I should have brought my ANR headsets!!
I agree with sarcasticpasti. There is an advantage to having an "all jet" airline from the perspective of a customer. They see turboprops as old, slow, loud, and unreliable. Now we all know that these turboprops (Saab, EMB, Dash) are somewhat new, faster than they are perceived, reliable, and workhourses for the airline. In terms of fuel burn, they would be good for an airline business plan. But lets not forget that:
The best business plan is the one that best appeals to the customers.
And that seems to be having an all jet fleet.
Now there are some markets that would be better served by turboprops.
1. Hawaii. "How long will an RJ last in the salt with 15 twenty minute segments a day, full blast to 16K, accel to 320 knots, and idle to landing."-HSLD
2. Tiny cities that just can't produce enough traffic for 50 seat RJ's, and are real close to the hub. Maybe the ERJ-135 can serve these cities, but 19 and 30 seat turboprops work well here.
All in all, I think you will see the big regionals phase out these turboprops over the next few years. The only exception I can think for this is Horizon who apparently likes turboprops.
My opinion.