Hyper-V Program Manager
There are a couple of interesting VHD updates that have recently come out:
Not only should VHDs be the way the programs are evaluated, it should also be the way they are installed.
Because the VHDs will need to be customized for the customer environment, this also has the side effect of improving the migration experience. Top example is Exchange/AD, where it's hard to change many things if they were set wrong at the initial install.