There are a huge amount of twits commenting on this with absolutely no knowledge of the NHS setup. The NHS does not mandate the use of IE6, the choice for its use is down to each trust (ie, county or major hospital.)
Also, please quit using every single virus outbreak as justification to use linux. Yes, the security of a defualt windows install is rubbish. No, installing Linux is not the solution everywhere simply because the software doesn't exist to be able to do it. The NHS is a point in case, there is no possible way to use linux for the entire of the NHS simply because none of the required apps actually run on it.
I've run linux myself, I don't really like Microsoft that much and I might use it in a business environment if it was a viable alternative. However, its not. By constantly blanket parroting "use linux" your doing real harm to the chance of linux ever getting ANYWHERE because when someone does suggest using it where it might work, we never manage to find out because people in IT have gotten so used to ignoring idiots sprouting "use linux!" that suggesting it is pointless because you get mentally lumped in the same boat as the idiots and ignored.
If you would actually start only proposing it only where it can actually be used then you MIGHT just find that linux gets used a bit more. Until then, what your doing just makes professionals that have well reasoned arguments for using it looks like quacks and your helping microsoft far more than they could ever manage with SCO or patent lawsuits in a hundred years.