I jumped ship -- the tipping point was the pulldown in PIT. I put up with the reservation migration, the dirty planes, the operational messes, and the first devaluation of the DM program because they still flew the most mainline flights where I needed to go. But once they no longer had the schedule advantage (and they never had the price advantage), I couldn't think of a reason to stick around. Now I've been with CO for a month and believe it or not I'm thrilled with EWR, because of the perspective of where I came from.
Naturally, the thought of doing it all over again with CO and UA potentially merging scares the heck out of me.