Open the email, and you’ll find that this bonus back is from a FarmVille VIP, who was given the opportunity to share a pack with their FarmVille neighbors. The packs themselves can be opened by clicking on the link in the email, as seen in the screenshot below.
Once you do, you’ll see the following page, which will ask for the code you’ll see in your email.
After redeeming your code, you’ll be given the chance to send packs to up to 30 of your FarmVille friends. Also, you’ll be eligible to receive 20% off any Farm Cash or Coin purchase in the next 72 hours. As for what’s inside the pack, you’ll have to reload the game to find out. In my case, I received 2 Whole Fuel Refills, a Totem Pole, a FarmHand and an Arborists.
From images we’ve seen, it appears that the decorative item (the Totem Pole) might be different for each user, as other images contain things like Bicycles. What items did you receive in your Friends and Family Packs?