Unfortunately the response leaves a lot to be desired — here's a precis
"In response to the concerns of many people regarding the security of Internet Explorer 6 and the use of this software by Government Departments the Cabinet Office can confirm that the Government takes internet security very seriously.
It is not straightforward for HMG departments to upgrade IE versions on their systems. Upgrading these systems to IE8 can be a very large operation, taking weeks to test and roll out to all users. To test all the web applications currently used by HMG departments can take months at significant potential cost to the taxpayer. It is therefore more cost effective in many cases to continue to use IE6 and rely on other measures, such as firewalls and malware scanning software, to further protect public sector internet users."
Sounds more like MBA spin than a professional and responsible attitude