Wear hat in public for the rest of your life > executed at Nuremberg > spend rest of life in Soviet military prison. Landa is pretty much the victor there.
I think that was one of Tarantino's points; that the wild, revenge-based violence of the IBs in the end failed to overcome a single villain's fiendish intelligence and world politics. They had to take a personal defeat in order to allow for Hitler's earlier death and ending the war.
Incidentally, and I am aware we are going way off topic for this thread, Landa's and the IBs actions would have ended up saving many, many German lives. Presumably, the death of Hitler and other senior Nazis would have likely meant Germany's surrender to the Allies much earlier. That likely would mean the bombing of Dresden wouldn't have happened, the bloody fight to the last man in Berlin wouldn't have happened, and the end of WW2 may have been been more favourable for the Western Allies, meaning Germany would not have been divided.