Any game made for a console will look and play great on that console because it was made for that. On the other hand, any game will play great on a computer because there are so many ways to configure it. I do agree that it's nice not having to play at a desk, but you can get a wireless keyboard and mouse and enjoy it also.
Another thing is that a console will be the same no matter how long it's out. You will never get better graphics or be able to make it faster. On the other hand, you can always upgrade computers, get faster components, and just generally customize a computer much more than a console.