I have now heard back from the officer in charge of the project who tells me:
The purpose of the pilots is to provide valuable feedback at an early stage, for example in relation to different service providers offering services on the new network. The rollout is highly technical and the pilots were selected in areas that could be upgraded relatively quickly.
Detailed planning and survey work is currently underway across the whole of Cornwall and the Isles of Scilly, and we are expecting to be able to announce a detailed rollout plan when it has been completed in Spring 2011. Because of the existing telecommunications infrastructure it was not possible to run the pilots in North or South East Cornwall, but there is a significant amount of upgrade work currently being undertaken in these areas to ensure that they feature prominently in the first phase of the main rollout.
That's good news. We were promised that the roll out would begin in the East and I look forward to the details of how this will happen in the Spring.