I did it this morning. Ordered the collectors edition with 25% off. Had to put something else in the cart to bring it over $100. There are a bunch of things out there for 2-3 bucks to put you over. My total is $83.21

The website says it can take up to 1 business day for you to get your beta key so don't freak out when you don't get it right away.

Quote: Online Customers (web delivery): A code and instructions on how to join the beta will be emailed within 1 business day of when your order was placed.