In 2002 e-on replied to a member who inquired why they did not accept American Express cards, that they were working on it. It is now 2009 and they are still working on it. I hope that gentleman was not holding his breath!
Come on e-on, do something about it. I know that the  Am Ex charge is a slightly higher rate than some of the other card providers, but that rate comes down with time and volume. In the seven years that they were working on it, it would now be a reasonable rate.