This post is a new beginning of my new Blogger account which has just switched few minutes ago. The process is very simple. All you have to do is to login using the Migrate login screen and follow the steps there (it's only two steps before you can have your account switched to use the new features of Blogger). After that, it will display the process and it will tell you via email when the process is done. When it's done and you're still at that page, it will let you visit your new dashboard where all of your account (from your old Blogger and Beta Blogger are combined and from this single dashboard, you can manage all of your Blogger account).
This post also answered my previous post about No Upgrade Option (Yet).
Here's the screenshots of the processes: