Hamilton, appearing on the BBC after his British GP win, queried (with his usual endearing lack of tact) where the proper trophy was. As I recall, the actual trophy is presented to the winner afterwards and Hamilton had it with him when he was interviewed on the BBC Forum, it's just that the plastic bric-a-brac one is used for the podium ceremony because, presumably, it looks better in the race sponsor's and FOM's opinion.
I think they've usually presented the traditional trophy at the podium and in teams' post-race celebrations they've had the sponsor trophy. Now they presented instead the sponsor trophy at the podium.