The Ryanair website loaded up slowly, then when I went through the process of a booking, the following message was shown:
"We regret, due to system slow down issues, we have been unable to display the tax inclusive fare box on this page, since 25/06/2008. We are currently working with our suppliers, including Navitaire to resolve these problems and hope to restore the tax, fees & charges inclusive display shortly."
Apart from that it seems to be working well. Perhaps because taxes are included initially that other website won't use Ryanair data?