Why would it be a 70D when the 7D is older?
It's hard to tell if it's going to be the 70D or the 7DII. Either one is possible.
The 60D is the 'weakest link' in Canon's lineup right now.
They need a strong seller at the $1K price point.
So, a new 70D priced at $900-1200 (USD) is a very good candidate for announcement - to boost sales.
The thing is, the 7D is selling for $1200 right now.
So, it's also possible that the 7DII might get announced first for $1600-1800, while the 7D remains on sale for $1200.
In this case the 60D will get discountinued until a replacement comes in the fall.
Nothing is certain, as we don't know what Canon's strategy is for their 1.6x lineup.