Update: If you look on the boxes for the new XBoxes, you can already find models with the 65 nm processor and 2 heatsinks.
For XBox360 Elites, anything with a MANUFACTURER LOT# of 0728 or higher has 65 nm processors and 2 heatsinks.
If you find MANUFACTURER LOT#s of 0724 or 0725, these have 2...