Just read the press release announcing the delivery of CO's first 737-900.
Anyways the 737-900s and all new deliver 737-800s will feature a 4th mid-cabin lav. For the 738 the seating config shifts from 14F/141Y to 18F/132Y.
So my questions: how many CO 738's currently feature this setup, and how soon will the entire fleet be retrofitted with the new interiors.
Secondly what was the reason behind this move? Obviously there are more premium seats, but with fewer seats in coach, why the extra can?