Third question: "Did you find anything?" Option 1: "Yes" => panic. Option 2: "No" => "Liar!".
You have to release all the details sometime, but the longer you wait, the more people suspect they aren't getting all the details (even if they are) and the larger the drama whirlpool becomes. Did "Kaminsky found a DNS bug, details will be forthcoming" accomplish anything? No, it was a giant clusterfuck.
As a side note, I think it's weird that in a "post-wikileaks" era people are arguing that an open source project named openbsd be less transparent.