Company car included in my offer letter. Have had a company car for 8 years. Instructed on 5 Dec 2008 not to enter into new lease (expiring 23 Jan 2009) because company car policy is being changed. As of 6 Jan, "new" policy still not in effect. What can/should I do?

I would assume that you would have until Jan 23 but it would be best to ask whoever would know exactly what is going on.