Compare The King's Speech to the Real King's Speech

Here's a video of the real stammer-filled speech King George VI gave at the opening of the British Empire Exhibition. It's similar to the speech that begins the Oscar-nominated movie The King's Speech. How faithful was the adaptation?

The stuttering doesn't begin in earnest until about two minutes into the clip. In the movie, he doesn't get 10 seconds into the recorded oration without messing it all up. If you haven't seen the movie yet, you can get a glimpse of Colin Firth delivering a speech at the beginning of the trailer below. How did he do? Does he deserve the Oscar or was he taking far too many liberties?

[BuzzFeed]