EDIT
I was initially skeptical of this story, as early reports gave no source for the letter.
Now it is clear that the story is direct from Apple.
Best of luck Steve. You will always be one of the glorious, persnickety, irascible titans of the IT world. You found an IT world that did not match your vision, and you changed the IT world to match you.
Your products and services are proudly used by hundreds of millions of people. We all have our own little packages of highly crafted world-leading industrial design and advanced technology.
Thanks to you.