Whatever they do for Greyhawk, I want there to be a deluxe edition that comes with lots of historical material. Maybe hire Jon Peterson (Game Wizards) to write a condensed history of how the game started, emphasizing the importance of Greyhawk and Blackmoore (which should be included as an adventure setting) in the creation and evolution of D&D. Really give Arneson, Gygax and friends their flowers, and keep that story alive for new generations of players.
I think that kind of deluxe edition would sell well, but I also think it is important to pass those roots on. D&D isn't just a game, it's a culture. The 50th needs to celebrate it as such.