Looks like the best laid plans of mice and men are plans easily laid low by a HummerGuy. The site all about the vehicular BJ is reporting via a standard embargo break that the 2008 Hummer H2
"...gets a larger 6.2 liter V8 with a six speed transmission - the horsepower increase hasn't been announced, but should be significant. The full third row seat is also new - Hummer has never offered more than a single seat in the rear area. The interior dash area has been updated to a more luxurious and clean looking control panel. It also appears that the front bumper has been changed to an aluminum colored finish. The leather choice has also been updated in 2008. These are some terrific advances to a vehicle that has not had a major update in 5 model years!"
And in addition to the pictures below, here's what he's got to say on the H3 Alpha:
"The 2008 Hummer H3 Alpha will have a 5.3 Liter V8 engine. Again, no specifics on HP gains just yet. That is by far the largest component of the update, but some drivetrain systems have been updated to support the increase in power. Similar to the H2 photos, there was a brushed aluminum looking front bumper that will replace the current black bumper. We didn't see many interior updates besides the Alpha badge on the steering wheel."
Now it'll have some power to move all that brushed aluminum around now, won't it? [Hat tip to Nathan!]