License upgrade?

Alright, I’ve gotten a project to a point where I want to try and publish it for Android. So I’m about to purchase the $400 android license. However, I know that the new Unity 4.0 iteration is around the corner. My question is if I were to purchase a license right now, would I have to pay some kind of upgrade fee for a license with the new version or would I be grandfathered in?

Also this is my first time publishing anything, I would be able to deploy my game to the Google Play Store with Unity correct?

You can’t buy a Unity 3 license at this point; the only thing you can buy is a Unity 4 license, which has the ability to run any previous version of Unity.