I was just now over at startrekonline.com and i was reading some of the great work they are doing with the backstory from Nemesis until the time the game is set.
In their latest update I read this:
http://www.startrekonline.com/timeline/2384
And Starfleet decides to transfer the Soong-type android B-4 to the custody of the Soong Foundation. The prototype android was deactivated after its discovery by the Enterprise-E in 2379, but foundation representatives say they hope to restore his full positronic functioning.
So since, as far as we can tell by the uniforms, there is some form of continuity between the game and the comic, could it be that the Data in Countdown is actually B-4 fixed by the Soong Foundation and with Data's memory and personality restored ?
I could see this happening.