IMO Stevie should leave, as pool will get a huge amount of money which I think they will need since Thaksin's investment is as good as dead now.
Moreover, we must not forget that no matter how good one player is, the team cannot revolve around that player alone.
I think that if in the worst case scenario that Gerrard wants to leave then either Pool raise their selling price higher or get some key players in like duff as a part-exchange.
Anyways, no use fretting over that now. Wait and see. In the meanwhile enjoy the rest of Euro 2004.