I don't know about STL being a weak market for them, it could be I honestly have no idea. I think we take the cake for the most rumors about what is going to happen to the airport so far I've heard:
-Jetblue hub
-Frontier mini-hub
-AirTran focus city
-US hub to replace PIT
-AA completely demolishing it
-new TZ service
-an LH flight to FRA, awhile back, but still
-Aer Lingus to DUB
-BA as a continuation from ORD
-HP buildup
I see maybe one of those coming true, and certainly not an Aer Lingus flight despit the rumors.