well uncharted 3 is undertracked, so it may do it eventually.
it could look like this by the end of things.
Uncharted: Drake's Fortune: 4.5 million
Uncharted 2: Among Thieves: 6.0 million
Uncharted 3: Drake's Deception: 6.5 million
Uncharted: Golden Abyss: 3.5 million
Total Lifetime sales: 20.5 million
Gears of War: 6.0 million
Gears of War 2: 6.5 million
Gears of War 3: 7.0 million
Total LT Sales: 19.5 million
so its definitely not out of the realm of possibility.
especially since the Uncharted dual pack has worked wonders for the sales of the first 2. $40 for 2 games is a great deal. and Uncharted has shown to have great legs