According to the morning news, negotiations regarding Opel "have broken down" for the time being.
Apparently, "the American side" (not clear if that refers to the Treasury or to GM itself) has suddenly come up with "new demands" amounting to an additional 300 m €. And the German government wants the investor or the US Treasury to provide "adequate collateral" for the 1.5 bn € bridge financing, and such collateral has so far not been offered.
It's hard to comment without knowing the exact details. But it sounds a bit comforting that Berlin is at least trying to get some sort of collateral, instead of just handing out the money.
Though of course the dynamics of this kind of negotiation process usually include lots of posturing before the parties finally give in at the last minute...
Edit/Update: Today's FTD says that internal GM projections foresee an Opel/Vauxhall EBIT of -3 bn US$ for the full year 2009. I suppose that's a partial answer to the question "What do they need all those guarantees for?"