Thanks to DJWG, a retail employee for this!
Very interesting picture that he took, with the various company-sensitive data taken out. Certainly looks legitimate to me.
It shows that the Xbox 360 Arcade is to drop on September 7th, 2008. That would be on a Sunday, when I do believe most flyers are printed to show new sales. This would be the debut week of NHL 09, and 1 week prior to Rock Band 2, and Star Wars: The Force Unleashed, which would be a very good time to release such a pricedrop....If memory serves me correctly, Microsoft dropped the price on the X360 last year the week before Madden launched.
Back from the dead, I'm afraid.