As I understand it, Southern or Network Rail or one of the other companies involved in running the trains owns the station, so the only way that something would get done is if they decided that they wanted to do so (and since Forest Hill is already heavily used, they probably don't see much of a business case for improvements).

Oyster readers are due to be implemented before too long though, after Citizen Ken (sorry, Mayor Ken) recently agreed to pay the rail companies ?20m to implement them by 2009 (if my memory serves me correctly).