ConservativeHome have a rough outline of the new Conservative Party policy towards the EU. While they will not look for the “unratification” of the Lisbon Treaty, they will seek to renegotiate the UK’s ties with the EU.
To be honest any renegotiation of ties will be a loss of influence for the UK. As areas that they opt-out on they cannot influence and they might have to go along with somethings due to access of the single market whether they want to or not.
Also if they do renegotiate then any future appointments of high powered posts could not be British, currently the UK have possibities for the two highest poistions. In two and half years they would have very little chance of getting anything that is availible.
The one thing this policy will do though, is keep the Conservatives united. A referendum on Europe or Lisbon could have split the Conservatives. This is the safest option availible to Cameron should he want to stay Prime Minister for a bit!