If over 60% of the airlines go for the 3-3-3, then I suspect CO will as well. But I really would like to have seen the 2-4-2 with a double arm rest in the center 2-2/2-2.

CO did once have 2-4-2 - that was on the A300. That was a nice configuration. F had 2-2-2, 4 rows on the A300.