If I remember correctly Fable III sold roughly 1.5 million units due to the 2011 holiday bundle, of which a digital copy of Halo: Reach was also bundled. So 8.89 + 1.50 = 10.39m, and that's not even including other digital sales so it's probably around 11 million. I bet GT5 won't even come within 1.5 million of that number. I think Halo: Reach will go on to sell 11.75-12.75m lifetime, although we'll never really know because we can't track digital copies sold. For GT5 I'd predict 8.50-9.25m lifetime.
I suppose it won't sell as well as previous GT games because it's widely considered disappointing and it now has a strong main competitor in Forza Motorsport 2/3/4 which has probably swayed a fair amount of previous GT fans like myself due to its higher quality, in my opinion.
Simple answer: No.