This is a "generic" thank you message sent by a research assistant to his friends after he got a new job. Notice, it's followed by a personal note, which he customized for each indivudual to whom he sent this message.
Here's the email version of his thank you note:
Greetings from the new Research Assistant at the Tempest Geology Institute! That’s right, I got the job!
Special thanks for getting me in the door with your buddy at Limestone Labs. Not only did Dave have great suggestions—he was my link to my new boss.
Here's an image of the hardcopy version of his thank you note: