The shame of it all is that leading up to the withdrawal being announced, there were already advanced plans in place to apply upgrades to the Concorde fleet with improved interior, and most importantly modifications to the engines to make them a lot quieter. These would have brought the Concorde experience right into modern standards (of the time), and opened up new routes, but sadly they never got to see the light of day.
I noticed in a previous comment BA were blamed for Concorde's demise. Whilst there may have been some elements within BA who weren't supportive, I think it's Air France with the most blood on their hands. See Mike Bannister's excellent 'Concorde' book for the full background.