WPF and Heat\Battery Life

I am considering developing an application that uses WPF for the UI and am a
little concerned about the issue of Heat Generation and reduced Battery Life
for Laptop users when the graphics card is in 3D mode.

Does WPF need to be used in 3D mode for this to be an issue? Or will all WPF
applications require the GPU to be fully active?

There are a lot of stories about people running Vista with Aero Glass on
their laptops having a machine that is scoldingly hot or much reduced
battery life. Is anyone aware of what the situation is expected to be like
when Vista ships? Are the drivers going to be improved so they downthrottle
the GPU\Video Memory? And if so will the same option be available for WPF
apps on XP?

The application in question would be used in a retail situation and if the
use of WPF resulted in 1. Not being able to use Laptops or 2. reduced
hardware lifetimes due to heat then I think this would rule WPF out.

What are peoples thoughts on this? I am sure Microsoft have plans for this
and maybe future video card generations will handle this much better, but I
hope this is not the "fix" MS has in mind.

Thanks.