I expect the high ISO in JPG to be better on the 70D vs 60D for several reasons; all new APS-C sensor, Digic 5+ processor to better apply noise reduction algorithms as noted in higher native maximum ISO of 12,800 vs 6,400, etc if the rumoured spec list is true on CR.
Plus it has a new Live focus AF supposedly 5X faster than current if you want to use Liveview for video, etc. 19 cross points would also be a big step up from 60D which only has 9.
Rumoured specs look very close to current 7D (or some may even be better) so I'd expect a 7D2 soon. Main thing missing on the 60D vs 7D for me is micro autofocus adjustment to fine tune lens to body, not sure if this feature will be added back to 70D.
Looks like 70D is a big step up from 60D in rumoured specs - question is what will price be?