I don't think SC4 will ever reach a million. The sales have pretty much dried up completely.
17- LittleBigPlanet
18- FIFA 09
19- Far Cry 2
20- MotorStorm: Pacific Rift
21- Star Wars: The Force Unleashed
22- Fallout 3
23- Resistance 2
24- Tom Clancy's EndWar
25- Madden NFL 09
Most of those are yet to be released, because frankly most games seriously slowed down by now and will take a while to reach a million.
Semi off topic: What does a game need to qualify for Greatest Hits? I know Oblivion's on the list with around 700k sales, but Uncharted has 1.86 million sales and is not on the list. Does it need to have been out for a certain amount of time? (It's been more than a year, hasn't it?)
EDIT: Sigma has 370k sales. What is it doing on Greatest Hits?