As you may guess, I get a lot of friends and family asking me to rebuild their PCs, and since automating system rebuilds is my speciality, I of course run MDT 2012 at home for these kinds of jobs, I just maintain a separate task sequence for retail installs. I set it up once, and I usually have to do very little work to kick of a rebuild for these people.
One problem I have with MDT 2012 and the new ADK is that when deploying retail windows installs, putting in a CD key is not my something I want to do until I’m happy with the deploy so to bypass the MDT key prompt in the lite touch wizard, use the generic install key on the OEM media found in the sources/product.ini file. Load the appropriate key into the customsettings.ini file using OverrideProductKey= and you’re good to go! Now, obviously, you can’t use this key to activate, it just automates yours install, but regardless, it lets you skip the step, and do something else while MDT repairs your uncle ted’s laptop.
On a side note: Mr. Barnes http://scriptimus.wordpress.com/2011/05/24/mdt-2010-managing-product-keys/ has a great guide on how this is done in the ini file for KMS servers in the enterprise.