Gyles Brandreth, Alan Titchmarsh, Michael Aspel and Eamomn Holmes are all currently in the frame. Of those I think Aspel is probably the best choice, but for me Tom O'Connor is still the best option. He's always good on Dictionary Corner, plus he used to do Crosswits so he understands the workload of a daily quiz show - I don't think Des Lynam did.