Hopefully, this will lead apps that have a gratis/lite/ad-financed version and a donation/premium/ad-free version to have unified versions where one can upgrade to the latter option inside the app.
Something like this is going to have an intense affect on app rankings in the Market as free apps won't lose their install rates as people decide to upgrade to the paid versions.
I hope not. I actually buy the ad-free version in many cases because I don't want to grant the permissions that the ad-financed version requests (frequently phone state & identity, GPS location, and internet access). If there's just one version, there will be no way for me to use the app without giving the application those permissions.