It's not Gamepad VS Keyboard+Mouse. Controllers (including Xbox360) work perfectly well with a PC. And playing on a bigger screen isn't a factor either, as any video card in the last 10 years can plug into a Large Format Display (TV). The PC always wins out technically speaking.
The only benefit game consoles have left is the ease of initial setup. Which, in my opinion, isn't that big of a deal anyway.
I've never played a game that I felt was better on a game console. Many that were better with wheels, analog sticks, force feedback, and huge screens from a couch; but those are all possible with a PC.
Some games are just not suitable for lounging with a gamepad. For instance:
- Civilization 4 vs Revolutions
- Age of Empires, Homeworld, Warcraft 3, Command & Conquer (any RTS really)
- First-person games of any kind are better with a mouse.
- Even racing games like Need for Speed are better when you can pick button placement and use a mouse when customizing a vehicle.