Well the next gen systems are basically computers in console form. But good gaming computers have much better specs then the next gen consoles. So while there will be games that have better graphics on the console then the PC. The potential is much higher on the PC. For instance my Crysis 3 copy on full settings looked alot better then the PS3 version of Crysis 3 did.
Final Fantasy 14 online beta looks alot better on my PC then when i play it on my PS3. So while that isnt the next gen system you are talking about it will likely be the same scenario in a few years.
Thats what I am thinking.
Consoles were always a computer in a console form. The ability to upgrade PC's is just what always separated the two in terms of performance.