Don't be an ATi fanboy, G80 is June/July while R600 is Q4. Those are establised release dates.
ATi ARE always late to the new generation. Happened with Radeon 9/GeForce FX, happened with Radeon X800/GeForce 6, happened with Radeon X1000/GeForce 7, and its going to happen again with R600/G80.