[Dr. Show-Me]

It's my guess that GM is not going to announce an STS/DTS replacement until after they secure low interest government loans.
Critics could say, "You don't need government loans if you're producing luxury, low mpg niche cars for the wealthy." or some variation of that.
But, after getting the loans, it could be GM, seeking to return to its heritage, an American success story, coming back from the dead.... ad nauseum. Politics dictate no DTS until after the loan guarantees.