According to online retailer Amazon, a Destiny Beta will be available in early 2014 for those who preorder the game. Here is what they had to say:
Pre-order “Destiny” and receive access to the upcoming beta. Beta will be available in early 2014 on the following platforms: PS4 system, PS3 system, Xbox One, and Xbox 360. Limited time only. While beta codes last. Internet connection is required. Amazon will email you your beta access code within 1 business days of you placing your pre-order. Offer valid when shipped and sold by Amazon.com. This offer will be extended to all existing pre-orders. Limited to one per customer order. Amazon reserves the right to change or terminate this promotion at any time. Here’s how (restrictions apply)
Sounds great to me! Make sure you preorder Destiny here.