Good thread! Bulk of my miles are TATL. I switched to CO last year but most recent flights (all domestic) have been back on DL simply for routing. I'm taking a bit of wait and see at this point. I'm not very happy with DL and the long list of downgrades we've had to endure compared to NW who was fairly customer friendly. The one thing that would keep me flying Skyteam is if DL can fix it's IT issues so that I can reliably book KLM/AF Y+ or if DL adds Y+ to their TATL flights. Otherwise CO will be getting at least all of my TATL biz.

BTW, as immature as it may sound, all else being equal (or even slightly favoring DL) I'll fly anyone but DL simply to take biz away from them. I don't like the way they run their company and I particularly don't like their lack of integrity with communications.