Kyle at HardOCp continues posting about the GTX680. Yes, it seems it's gonna be called 680.
This is what he says:
"GK104 will be 680.
Seeing some benchmarks show 7970 in the lead, mostly in tessellated situations there, other "normal" synthetic 3D benchmarks and gaming benchmarks show 680 faster. Driver advancements still happening as well for 680."