I hate people who criticize the X-Box controller for either its size, or the giant "X" jewel in the middle. It beats the shit out of any other controller out there. You're right about the keyboard/mouse thing, but some games do go quite flowingly with a game pad.
And Death, remember, not everyone can afford a top-of-the-line-for-now computer
For the average player, the glory of ultimate preformance is limited. You'll have you're fun with Half-Life 2, though.