My understanding from a meeting with LOROL on 4 March is that there are no immediate plans to sell monthly or annual oyster cards froim the station as the Oyster cards have to be registered (and they will not have the facilities to do this).
Shere had run into problems getting accreditation for their Ticket Machines, which had delayed installation of Oyster vending facilities at the Ticket Offices. However, Oyster Vending facilities for PAYG/Weekly travelcards will be available by 23 May 2010, possibly earlier. (This is a contractual obligation with TfL)