I just checked out the game's site, and found that they're giving away the dev only paint job if you sign up for their newsletter. Dunno how long it'll be up, but if you bought this game, chances are you wouldn't mind being on the newsletter anyway.
Limited time Double Fine paintjob
I signed up when it was announced on twitter. Still not paintjob.
Around 3pm on the business day after you sign up, excluding today (because we were drinking at Giant Bomb), we'll post the new names to XBL, and you'll get the paint job in your inventory.
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