Well, I read the relevant passages (here, numbers 151-154) and discovered for myself that actually there are a lot of provisos, safeguards and limitations as to who can authorise it and for what reasons, to what extent the data can be copied, and the responsibilities of the people authorising it. None of this is mentioned in any of the accounts on my friends list or on the NO2ID website.
Now, don't get me wrong, it's definitely a significant attack on the Data Protection Act, but NO2ID reads too much like the Daily Mail to me, dealing in fearmongering before full facts.
I shan't be writing to my MP about this issue because I don't believe the powers granted are over the top. What I do disagree with is the underhand way the powers are being introduced, and the fact they feel it's necessary to degrade a previous act rather than simply state up front that any data you give may be used for other reasons under particular circumstances (usually if you are being investigated for criminal activity, from what I can work out).