Yes, the "iPhone 3G is dead" rumors are flying fast, and our latest entry is hardly a rumor: Apple's online store currently lists the solitary 8GB iPhone 3G next to the full iPhone 3GS crop, but there's no longer a tasty "select" button below it. Usually if something's out of stock on the Apple store it will just say so, along with a projected time of delay, but with the 4G presumably around the corner this could indeed be marking the end of the 3G's last stand.
[Thanks, J]