It still makes sense to me that the 7d2 could be the FF offering. But, there is also a good argument for the 70D to be FF.
But if this is the competition:
New/updated Nikon D600 specifications:
24.7MP full frame sensor
Weight: 760g (850g with battery and memory cards), the D800 weights 900g
3.2" LCD with 921K dot with ambient sensor control
HDMI output
Video compression: H264/MPEG-4
Full HD with 30p, 25p, 24p, HD with 60p, 50p, 30p, 25p
Viewfinder coverage: 100% for FX , 97% for Dx
The Nikon D600 will have built-in AF motor
The body most probably will be weather sealed
The D600 may not have built-in GPS as initially reported
ISO range: 100-6400 (with Lo-1 ISO 50 and Hi-2 ISO 25,600)
39 AF points (with an option of 11 AF points), 9 cross-type AF points
AF face detection
Exposure compensation: ±5 EV (same as the D800)
The D600 will probably use the EN-EL15 rechargeable Li-ion battery
If that's what the d600 is going to look like, then I'd say canon may be screwed if the the entry FF doesn't have some pro featured (like weather sealing). Canon has kind of forced themselves into a hole right now where they have to do something bold to stay competitive. Maybe nikon is seriously gambling, cause if those specs are retail price of $1500, they are mst certainly selling it at a loss to keep themselves relevant. Does a polycarb ff70d stand a chance?

can a ff super rebel make it (the ef-s glass issue is way more valid for the XXd series)..
If canon moves the 7D into FF territory, then they can for the firswt time really say that they xd series is their pro FF series.
From what I have heard, in Japan the number 6 is bad mojo, so its doubtful that they'd name anything with a 6 and no 0 after the 6.
no way the entry FF is called the 3d - 3D would have to fit in between the 1d and the 5d series, and if the rumors of a high MP body are true, the 3D would probably be that.
When it comes down to it though, we're all just have to sit and wait to see what actually happens!!!