Other Middle East and Africa Frequent Flyer Programs - Gulf move from LHR T3 to T4

2.2. Changes at London Heathrow
If you are flying to or from London on Gulf Air, we wish to bring to your attention that all our flights will arrive and depart in Terminal 4 at London Heathrow, effective 29th October 2009. For departure, please note that check in will be within Zone E at Terminal 4.

Wonder whether there will be a dedicated lounge or a shared one?

AFAIK, there is a new lounge to be opened, designed by James Park Associates. Not sure which lounge they've taken over though. Lounge is expected to open VERY soon.
Can't wait for the pics!