Space Shuttle Discovery Launch Postponed to no Earlier than November 30, SpaceRef
“NASA has decided to postpone the launch of Discovery to no earlier than November 30. This is a result of the hydrogen leak that occurred early in tanking of the shuttle external tank. It turns out there also was a crack in the foam of the external tank.”
Keith’s note: There are lots of NASA planes headed back to JSC and Stennis/MAF right now (see FlightAware)