Update: Reader Josh points out Stan Lee is only playable if you pre-order the game through Amazon. Below is the description:
Pre-order The Amazing Spider-Man, for PS3 or Xbox 360 and get the Amazon exclusive Stan Lee Adventure Pack. Voiced by Stan Lee himself, you'll web-sling through NYC as Lee to collect missing pages of his latest script. Collect them all to unlock a surprise reward.
Offer valid on all existing pre-orders. Access code will be e-mailed within two business days after your order ships. Offer valid when shipped and sold by Amazon.com, while supplies last. Limited to one per customer. Please read the PlayStation Network and Xbox Live terms of use.
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Marvel Comic's Stan Lee is a playable character in The Amazing Spider-Man, the upcoming game from Beenox and Activision. Get a look at him swingin' around town.
His character is fully voiced and has "just about" all the powers Spider-Man has in the game. The Amazing Spider-Man is due out on June 26.