Activision poses us this question in their cringeworthy announcement trailer for GoldenEye 007 on Wii.
Since you asked, there's rather a lot of reasons that a game could become regarded as a classic. In GoldenEye's case: a robust control interface solution which proved that the FPS genre was viable on console platforms; the innovative approach to singleplayer difficulty levels based around increasing the number and complexity of mission objectives; the 4-player multiplayer mode being completely unprecedented for a shooter on console; the skill with which encounters were crafted across extremely open-ended level designs; and many more reasons, I'm sure, largely owing to the talent of the developers at Rare. I don't think the magical powers of the title and film license are generally considered to be high in that list.
It's like history is repeating itself, not necessarily in the way they intend.
That's two short posts of pure jaded cynicism in a row, so next time I'll make sure to talk about design or something.