Sorry to keep bringing this back, especially since I seem to be the only person interested in this, but I found the CO copy of my receipt a bit funny when compared with the screenshot of my reservation from CO.com that I posted over the weekend.

Clearly the flight is now a UA flight (not even United Express, as the receipt says Skywest is dba United Airlines, Inc.)!

Sadly, this flight is apparently under full CO "COntrol," as channa would put it. CO.com wants $69 for ELR seats on this baby jet, $79 to sit in the exit row. UA.com wants $29 for E+ on a separate ORD-PHX flight I have booked. I wish I could get UA pricing for this "UA flight."