What I would suggest is to forward the email you got to
spoof@paypal.com. They will tell you if the offer is valid or it is just a phishing email. I would NOT click on any link in such emails until I make sure that it is actually from PayPal.
On Edit: this is from the official PayPal website. Have a look:
https://www.paypal-promo.com/holiday/slider/index.html