Vista Tutorial - Windows Aero requirements and development

I've been running Windows Vista Beta 2 build 5384.4 on a desktop machine with
a GeForce FX5200 graphics card, (128 bit, 256MB graphics RAM) and it runs
Windows Aero perfectly. About 6 months ago, I purchased a brand new notebook
computer with only 64 MB graphics RAM. I know that currently, Windows Aero
needs at least 128 MB graphics RAM to run properly. Obviously, it's no
problem to switch the graphics card on a desktop machine, but not at all
possible on a notebook. Even to this day, I found that about 50% of brand new
notebook computers have less than 128MB graphics RAM, that can't be upgraded
unless you choose a higher performance product line of notebook machines,
which sometimes vary $500-$1000 in price. Are the hardware requirements for
Windows Aero, such as the minimum amount graphics RAM needed, still subject
to change before it's finally shipped, and out of the shelves available to
consumers?