I just saw this article the other day. It's not much, but apparently the marketing manager for the new Fusion will neither confirm or deny the possibility of a high-performance Fusion variant. I think most of us were thinking along the lines of the 3.5L EcoBoost V6 from the Taurus SHO, but even the non-turbo 3.7L V6 from the Mustang would be fun (which is probably more likely since it's an option on the new MKZ). She says people have been asking and the platform can support it, so we can only hope a big engine will be a possibility in the future (2014 models?).
Article: Exclusive: Ford’s marketing manager overviews new Fusion, hints at Fusion SHO possibility