I think before we even consider reintroducing one of the top predators it would be a good idea to find out if we can be succesful at re-introducing a slightly less emotive species - the Beaver being a prime example. That's caused enough of a headache!
I love the thought of wolves back in Britain, and lynx, but one step at a time me thinks.
Seeing as we seem to struggle with the species we've got (both native and non-native) it may take a while.