Could you cancel my fingerprints while I cut up my eyeballs please?

The UK and US are getting biometric ID cards.

Regardless of your opinion of national ID schemes, it seems to me that a biometric based system is just asking for unnecessary extra trouble.

A quick Google suggests that it's already possible to fake a fingerprint scan with relative ease which isn't a good start.
Let's give the Government the benefit of the doubt and assume that:
  1. They can improve scanners such that the existing fingerprint hole can be plugged.
  2. Retina scanners are not currently foolable. 1
Given the length of time these systems would have to be in place to be cost effective (ha!), it's almost inconceivable that the scanning technology will not be outstripped by some deception technology during its lifetime.

Now we're reliant on people taking the scans to be vigilant to spoofing methods again, and we know for a fact that that won't happen.

So what do I do in this future world of perfect global identification when someone has my identity? I won't be canceling my existing ID and cutting it up because it is, well, me.2

I'd really rather like this question answering.

[1] Googling for fake retinal scans didn't find similar pages, but that's not to say they don't exist.

[2] Of course with biometric ID, other people have an interest in cutting you up, but that's another story.